The Winter Fortress

The Epic Mission to Sabotage Hitler's Atomic Bomb

Neal Bascomb

• Publisher: Mariner Books
• Year: 2016
• ISBN:
  9780544368064
• Topic: History
• Subtopic: World War II
• Index: History

From the internationally acclaimed, best-selling author of Hunting Eichmann and The Perfect Mile, a World War II spy adventure set in Norway that draws on top-secret documents and memoirs of the saboteurs. In 1942, the Nazis were racing to complete the first atomic bomb. All they needed was a single, incredibly rare ingredient: heavy water, which was produced solely at Norway's Vemork plant. Under threat of death, Vemork's engineers pushed production into overdrive. If the Allies could not destroy the plant, they feared the Nazis would soon be in possession of the most dangerous weapon the world had ever seen. But how would the Allied forces reach the castle fortress, set on a precipitous gorge in one of the coldest, most inhospitable places on earth? Based on a trove of top-secret documents and never-before-seen diaries and letters of the saboteurs, The Winter Fortress is an arresting chronicle of a brilliant scientist, a band of spies on skis, perilous survival in the wild, Gestapo manhunts, and a last-minute operation that would alter the course of the war. "Riveting and poignant... The Winter Fortress metamorphoses from engrossing history into a smashing thriller... Mr. Bascomb's research and, especially, his storytelling skills are first-rate."— Wall Street Journal

 

Part I

1

The Water

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ON FEBRUARY 14, 1940, Jacques Allier, a middle-aged, nattily dressed banker, hurried through the doors of the Hotel Majestic, on rue la Pérouse. Situated near the Arc de Triomphe, the landmark hotel had welcomed everyone from diplomats attending the Versailles peace talks in 1919 to the influx of artists who made the City of Light famous in the decade that followed. Now, with all of France braced for a German invasion, likely to begin with a thrust through Belgium, and Paris largely evacuated, a shell of its former self, conversation at the hotel was once again all about war. Allier crossed the lobby. He was not there on bank business but rather as an agent of the Deuxième Bureau, the French internal spy agency. Raoul Dautry, the minister of armaments, and physicist Frédéric Joliot-Curie were waiting for him, and their discussion involved the waging of a very different kind of war.

Joliot-Curie, who with his wife, Irène, had won the Nobel Prize for the discovery that stable elements could be made radioactive by artificial or induced methods, explained to Allier that he was now in the middle of constructing a machine to exploit the energy held within atoms. Most likely it would serve to power submarines, but it had the potential for developing an unsurpassed explosive. He needed Allier’s help. It was the same pitch Joliot-Curie had given Dautry months before, one made all the more forceful by the suggestion that the energy held within an ordinary kitchen table, if unlocked, could turn the world into a ball of fire. Allier offered to do whatever he could to help the scientist.

Joliot-Curie explained that he needed a special ingredient for his experiments—heavy water—and that there was only one company in the world that produced it to any quantity: Norsk Hydro, in Norway. As an official at the Banque de Paris et des Pays-Bas, which owned a majority stake in the Norwegian concern, Allier was ideally positioned to obtain whatever supplies Norsk Hydro had at its Vemork plant as quickly and discreetly as possible. The French prime minister himself, Édouard Daladier, had already signed off on the mission.

There was one problem, Allier said. Only a month before, the chief lawyer for Norsk Hydro, Bjarne Eriksen, had visited him in his Paris office. According to Eriksen, the Germans were also interested in the production at Vemork. They had placed a number of orders and had suggested that they might need as much as two tons of heavy water in the near future. Startled by the demand for such vast quantities—and denied any information about how the material might be used—Norsk Hydro had yet to fulfill more than twenty-five kilograms of these orders.

This report troubled Dautry and Joliot-Curie deeply. The Germans must be on the same track with their research. Allier needed to move—and fast—to secure the stock before the Germans did. If there was trouble in bringing it out of Norway, he was to see that the heavy water was contaminated, thus rendered useless for experiments.

Two weeks later, Allier headed across the vast hall of Paris’s Gare du Nord and boarded a train to Amsterdam. He was traveling under his mother’s maiden name, Freiss. Concealed in his briefcase were two documents. One was a letter of credit for up to 1.5 million kroner for the heavy water. The other gave him the authority to recruit any French agents required in smuggling out the supply. Short of the false beard, Allier felt like he had all the accouterments of a hero in the spy novels he loved.

From Amsterdam he flew to Malmö, Sweden, then took a train to Stockholm. There he sat down with three French intelligence agents, tasking them to meet him in Oslo a few days later. Early on March 4, Allier traveled by train to the Norwegian capital, arriving into Eastern Central Station. At the French Legation, he learned that his cover was already blown. An intercepted message from Berlin’s spy agency, the Abwehr, had been deciphered. “At any price,” it read, “stop a suspect Frenchman traveling under the name of Freiss.”

Allier was undeterred. He left the legation and rang Norsk Hydro from a public phone booth. Within the hour, he entered the company headquarters at Solligata 7, a short distance from the royal residence of King Haakon VII. In a meeting with Dr. Axel Aubert, Allier made his offer to buy the company’s stocks of heavy water. He said nothing about their intended use, unsure that he could trust Aubert. The tough, long-standing director general, who looked like he chewed stones for breakfast, was clear: his sympathies were with France; he had refused the Germans any great quantities of heavy water, and he would provide Allier with whatever he needed.

The next day, Allier traveled by car to Vemork, one hundred miles from the Norwegian capital. Aubert followed. Their arrival was unannounced.

For thousands of years, water had run plentifully throughout the high wilderness plateau of the Hardangervidda in Telemark, a region west of Oslo. Much of this water, a vast flow, descended from the Vidda into its natural reservoir at Lake Møs. Then the river Måna carried the water for eighteen miles through the steep Vestfjord Valley to Lake Tinnsjø.

The river’s flow changed when Norsk Hydro, a burgeoning industrial giant, built a dam at the lake’s outlet in 1906. The company redirected the water through tunnels blasted out of the rock, which ran for three miles underground before they reached the Vemork power station. From there, the water fell 920 vertical feet through eleven steel pipelines into turbine generators that produced 145,000 kilowatts of electricity. It was the world’s largest hydroelectric power station.

A fraction of the water, roughly sixteen tons an hour, was then directed into a hydrogen plant, also the world’s largest, thirty feet away on the edge of the cliff. There it flowed into tens of thousands of steel electrolysis cells, which consumed almost all of the power generated at the station. Currents of electricity running through the cells split the water’s two hydrogen atoms from its lone oxygen one. These separated gases were then pumped down to chemical plants in Rjukan, at the base of the valley. A company town, Rjukan had seven thousand residents most of whom worked for Norsk Hydro. The hydrogen was primarily used to make fertilizer—a huge market.

A fraction of this water, which had by now coursed from the Vidda to Lake Møs through tunnels, then pipelines, then electrolysis cells, was sent through a cascade of specialized electrolysis cells that terminated in a basement cellar at Vemork. The water was then reduced and further reduced until it amounted to a steady drip similar in output to a leaky faucet. This water was now something unique and precious. It was heavy water.

The American chemist Harold Urey won the Nobel Prize for his 1931 discovery of heavy water. While most hydrogen atoms consist of a single electron orbiting a single proton in the atom’s nucleus, Urey showed that there was a variant, or isotope, of hydrogen that carried a neutron in its nucleus as well. He called this isotope deuterium, or heavy hydrogen, because its atomic weight (the sum of an atom’s protons and neutrons) was 2 instead of 1. The isotope was extremely rare in nature (.015 percent of all hydrogen), and there was just one molecule of heavy water (D₂O) for every 41 million molecules of ordinary water (H₂O).

Building on Urey’s work, several scientists found that the best method for producing heavy water was electrolysis. The substance didn’t break down as easily as ordinary water when an electric current ran through it, so any water remaining in a cell after the hydrogen gas was removed was more highly concentrated with heavy water. But generating the substance in any quantity demanded tremendous resources. A scientist noted that in order to produce a single kilogram (2.2 pounds) of heavy water, “50 tons of ordinary water had to be treated for one year, consuming 320,000 kilowatt hours [of electricity], and, then, the output had a purity no better than about ten percent.” That was a lot of electricity for a low level of purity in a very small quantity of deuterium.

In 1933 Leif Tronstad, a celebrated young Norwegian professor, and his former college classmate Jomar Brun, who ran the hydrogen plant at Vemork, proposed to Norsk Hydro the idea of a heavy water industrial facility. They weren’t exactly sure what the substance might be used for in the end, but as Tronstad frequently said to his students, “Technology first, then industry and applications!” They did know that Vemork, with its inexhaustible supply of cheap power and water, provided the perfect setup for such a facility.

They matched the plant’s natural advantages with an ingenious new design for the equipment. An early working plant, designed by Tronstad and Brun, had six stages. Think of a group of cans stacked in a pyramid. Now picture that pyramid upside down, with the single can at the bottom. In the Tronstad/Brun design, water flowed into the top row of cans—really 1,824 electrolysis cells, which treated the water (mixed with potash lye as a conductor) with a current. Some of the water was decomposed into bubbles of hydrogen and oxygen gas that were vacated from the cells, and the remainder, now containing a higher percentage of heavy water, cascaded down to the next row of cans in the pyramid (570 cells). Then it repeated the process through the third (228 cells), fourth (20 cells), and fifth (3 cells) rows of electrolysis cells. However, by the end of the fifth stage, with a huge amount of time and power exhausted, the cells still contained only 10 percent deuterium-rich water.

Then the water cascaded into the bottom can of the pyramid. This sixth and final phase was called the high-concentration stage. Set in the cavernous, brightly lit basement of the hydrogen plant, it actually consisted of seven unique steel electrolysis cells lined up in a row. These specialized cells followed a similar cascade model to concentrate the heavy water in each cell. But they could also recycle the gaseous form of deuterium back into the production process, while it was essentially wasted in the other stages. As a result, the heavy water concentration rose quickly from one cell to the next. By the seventh, final cell in this high-concentration stage, the slow, steady drip had been purified to 99.5 percent heavy water.

When the Vemork plant started production in earnest using this method, scientists around the world heralded it as a breakthrough, even though heavy water’s application remained uncertain. Because it froze at four degrees Celsius instead of zero, some joked it was only good for creating better skating rinks. Tronstad, who served as a consultant to Norsk Hydro and left the running of the plant to Brun, believed in the potential of heavy water. He spoke passionately of its use in the burgeoning field of atomic physics, and of its promise for chemical and biomedical research. Researchers found the life processes of mice slowed down when they were given minute amounts of heavy water. Seeds germinated more gradually in a diluted solution—and not at all in a pure one. Some believed that heavy water could lead to a cure for cancer.

Vemork shipped its first containers of heavy water in January 1935 in batches of ten to one hundred grams, but business did not boom. Laboratories in France, Norway, Britain, Germany, the United States, Scandinavia, and Japan ordered no more than a few hundred grams at a time. In 1936 Vemork produced only forty kilograms for sale. Two years later, the amount had increased to eighty kilograms, a trifling amount valued at roughly $40,000. The company placed advertisements in industry magazines to little avail: there simply wasn’t sufficient demand.

In June 1939 a Norsk Hydro audit of this small sideline business showed it to be a loser. Nobody wanted heavy water, at least not enough to make it worth the investment, and the company abandoned the venture.

But only months after Brun shut off the lights in the basement and dust started to gather on the seven specialized cells in the high-concentration room, everything changed—and quickly—just as it had in the field of atomic physics.

For decades, scientists had been plumbing the mysteries of “atoms and void,” which was how the ancient Greeks described the makeup of the universe. In dark rooms, experimenters bombarded elements with subatomic particles. Theoreticians made brilliant deductions on the blackboard. Pierre and Marie Curie, Max Planck, Albert Einstein, Enrico Fermi, Niels Bohr, and other scientists discovered an atomic world full of energy and possibilities.

The English physicist Ernest Rutherford observed that heavy, unstable elements such as uranium would break down naturally into lighter ones such as argon. When he calculated the huge amount of energy emitted during this process, he realized what was at stake. “Could a proper detonator be found,” he suggested to a member of his lab, “a wave of atomic disintegration might be started through matter, which would indeed make this old world vanish in smoke . . . Some fool in a laboratory might blow up the universe unawares.”

Then, in 1932, another English scientist, James Chadwick, discovered that proper detonator: the neutron. The neutron had mass, but unlike protons and electrons, which held positive and negative charges respectively, it carried no charge to hinder its movement. That made it the perfect particle to send into the nucleus of the atom. Sometimes the neutron was absorbed; sometimes it knocked a proton out, transforming the chemical element. Physicists had discovered a way to manipulate the basic fabric of the world, and with this ability, they could further investigate its many separate strands—and even create some of their own.

Using radon or beryllium as neutron sources, physicists began flinging neutrons at all kinds of elements to produce changes in their nature. Led by the Italian Fermi, they found this process particularly effective when the neutrons had to pass through a “moderator” of some kind, which slowed their progress. Paraffin wax and plain water proved to be the best early moderators. Both contained lots of hydrogen, and when these hydrogen atoms collided with the neutrons (which had the same mass), they stole some of their speed, much like when two billiard balls collide. Bombarding uranium with neutrons in this manner brought the most mysterious results, including the unexpected presence of much lighter elements.

In December 1938 two German chemists, the pioneering Otto Hahn and his young assistant Fritz Strassmann, proved that a neutron colliding with a uranium atom could do more than chip away at its nucleus or become absorbed within it. The neutron could split the atom in two—a process called fission. By early January 1939, word of the discovery had spread, bringing great excitement to the field of atomic research: Why, how, and to what effect had the uranium atom split?

Springboarding off an observation by the Danish theorist Niels Bohr, physicists realized that the uranium atom’s nucleus had acted like an overfilled water balloon. Its “skin” was stretched thin by the large number of protons and neutrons inside, and when a neutron was shot into it, it formed a dumbbell: two spheres connected by a thin waist. When the tension on the skin finally became too much, it snapped, and the two spheres—two lighter atoms—were flung apart with tremendous force, an amount equal to the energy that had once held the nucleus together (its binding energy). Researchers were quick to come to a figure, too: 200 million electron volts—enough to bounce a single grain of sand. A tiny amount, perhaps, but given that a single gram of uranium contained roughly 2.5 sextillion atoms (2.5 x 10²¹), the numbers alone obscured the potential energy release. One physicist calculated that a cubic meter of uranium ore could provide enough energy to raise a cubic kilometer of water twenty-seven kilometers into the air.

The atom’s potential power became even clearer when scientists discovered that splitting the uranium nucleus released two to three fast-moving neutrons that could act as detonators. The neutrons from one atom could split two others. The neutrons from these two split four more. The four could cause the detonation of eight. The eight—sixteen. With an ever-increasing number of fast-moving neutrons flinging themselves about, splitting atoms at an exponential rate, scientists could create what was called a chain reaction—and generate enormous quantities of energy.

Which prompted the obvious question: To what purpose? Some conceived of harnessing the energy release to fuel factories and homes. Others were drawn to—or feared—its use as an explosive. Within a week of Hahn’s discovery, American physicist J. Robert Oppenheimer sketched a crude bomb on his blackboard.

Fermi, who had immigrated to the United States, trembled at the thought of what might come. Staring out the window of his office at Columbia University, he watched students bustling down the New York sidewalks, the streets crowded with traffic. He turned to his office mate, drew his hands together as if holding a soccer ball, and harked back to the words of Rutherford. “A little bomb like that,” he said solemnly before looking back outside, “and it would all disappear.” Given the aggression shown by Nazi Germany by the end of summer 1939, such a bomb, if it could be built, might be needed in a world on the precipice of war. Plans to obtain it were rapidly put together on both sides.

By annexing Austria and occupying Czechoslovakia, Adolf Hitler had managed to pursue his goals without a fight until September 1, 1939, when at 4:45 a.m. his 103rd Artillery Regiment sent its first “iron greetings” into Poland. Panzer tanks swept across the border and bombers shot eastward overhead. The German Blitzkrieg had begun and, Hitler promised, bombs would be met with bombs.

Britain and France responded with a declaration of war. On September 3, Winston Churchill, First Lord of the Admiralty, rose in the House of Commons and said, “This is not a question of fighting for Danzig or fighting for Poland. We are fighting to save the whole world from the pestilence of Nazi tyranny and in defense of all...

Table of contents

• Title Page
• Contents
• Copyright
• Dedication
• Maps
• List of Participants
• Epigraph
• Prologue
• Part I
• The Water
• The Professor
• Bonzo
• The Dam-Keeper’s Son
• Open Road
• Part II
• Commando Order
• Make a Good Job
• Keen as Mustard
• An Uncertain Fate
• The Lost
• Part III
• The Instructor
• Photos
• Those Louts Won’t Catch Us
• Rules of the Hunter
• The Lonely, Dark War
• The Storm
• Best-Laid Plans
• The Climb
• Sabotage
• Part IV
• The Most Splendid Coup
• The Hunt
• Phantoms of the Vidda
• A National Sport
• Target List
• Cowboy Run
• Part V
• Nothing Without Sacrifice
• Five Kilos of Fish
• The Man with the Violin
• A 10:45 Alarm
• Victory
• Epilogue
• Acknowledgments
• Notes
• Bibliography
• Index
• Sample Chapter from THE ESCAPE ARTISTS
• Buy the Book
• About the Author
• Connect with HMH