The Winter Fortress Read online

  Now, as the Whitley approached the drop point, Skinnarland ran through what he had been taught: “Feet together and launch off gently. Relax every muscle when you hit the silk and—” It was one thing to parachute in daylight, the landing zone flat and clear to the eye. It was another to fall into a midnight blackness over territory pocked with rocks, precipices, and frozen—but perhaps not frozen enough—lakes. Skinnarland was tough, but he was not fearless.

  At 11:44 p.m. his drop dispatcher, Sergeant Fox, called him to action stations. Fox sent the large tube container of supplies out first. Then Skinnarland edged up to the hole, reluctant to dangle his legs over oblivion. Fox raised his arm and then lowered it, signaling Skinnarland to go. Skinnarland hesitated, then shouted out that they were not in the right zone, but his words were lost in the growl of the bomber’s engines. Fox signaled him again. Skinnarland hesitated still. For twenty minutes, the plane circled around the drop site, Skinnarland unsure whether they were over the right spot, unsure of himself. At last Fox approached his reluctant charge and yelled that they lacked the fuel to fly much longer.

  “We’re going back,” Fox said.

  “No, I’m jumping,” Skinnarland responded, though he remained still.

  In the small container by his feet, among the presents designated for his organization, was a silver-plated spoon with a painting of the Houses of Parliament on its handle. If he survived the jump, he planned on giving it to his mother.

  Finally, a few minutes after midnight, Skinnarland took a deep breath and dropped into the dark sky.

  5

  Open Road

  * * *

  THE TUBE ALLOYS COMMITTEE met on April 23, 1942, at Old Queen Street in London, gathering in a seventeenth-century townhouse with tall windows and a fine view of the early spring in St. James’s Park below. As usual, the scientists, led by Wallace Akers, former research director at Norsk Hydro’s rival Imperial Chemical Industries (ICI), had a lot to talk about: experimental work on fusing a bomb, cooperation with the Americans, the expansion of a model isotope-separation plant, and further orders of uranium oxide. As at every meeting, they discussed the Germans, but this time with heightened urgency.

  Since 1939 the British scientific establishment had feared the Nazis would obtain an atomic bomb. Hitler’s invasion of Poland, then his boast that he would soon “employ a weapon” for which there was no answer, made the danger that much more imminent, prompting Sir Henry Tizard, head of the Air Ministry’s research department, to investigate the production of a British bomb. As the government’s chief scientific adviser, charged with developing new technologies like radar, Tizard’s word carried a lot of weight. And so the inquiry began.

  Two young physicists, Otto Frisch and Rudolf Peierls, both Jewish refugees from Germany, put the British firmly on their path. On March 19, 1940, their report, “On the Construction of a Super Bomb,” landed on Tizard’s desk like a thunderclap. Frisch and Peierls detailed how little more than one pound of pure U-235—divided into two (or more) parts that were then smashed together at a high velocity—would initiate an explosion that would “destroy life in a wide area . . . probably the center of a big city . . . at a temperature comparable to the interior of the sun.” Then they raised the specter that German scientists might soon “be in possession of this weapon.” The only way to counter this threat, they concluded, was for Britain to have the technology as well.

  The following month, the British government launched the MAUD Committee. Exploratory research began with some of its preeminent scientists, as well as Peierls and Frisch. Foremost, they proposed building a plant to separate rare U-235 from its cousin U-238. This plant would cost as much as a battleship. In July 1941 the group delivered a road map for an atomic bomb program. Tizard remained skeptical, particularly as to its cost. He thought it best the Americans handle everything. But the project now had a champion in Lord Cherwell, the Oxford physicist who Churchill said could “decipher the signals from the experts on the far horizons and explain to me in lucid homely terms what the issues were.” On August 27, 1941, Cherwell recommended moving forward with producing the first bomb within two years. The experts gave the project 10–1 odds of success, but Cherwell told the prime minister that he would bet little more than “even money.” He continued, “It would be unforgivable if we let the Germans develop a process ahead of us by means of which they could defeat us in war or reverse the verdict after they had been defeated.”

  Churchill wrote to his War Cabinet, asserting, “Although personally I am quite content with the existing explosives, I feel we must not stand in the path of improvement.” The cabinet agreed, promising “no time, lab-our, material or money should be spared in pushing forward the development of this weapon.” Thus the Directorate of Tube Alloys was formed.

  Throughout this period, fears over the German bomb persisted. From far and wide came whispers, rumors, threats, and fact—which, mixed together, made for the typically confusing brew that governments called “intelligence.” Two German pilots were overheard on a tram speaking about “new bombs” that were “very dangerous” and had the power of an earthquake. One German émigré physicist warned that there was pressure from high within the Nazi government to build a bomb and that the Allies “must hurry.” Another warned that the Wehrmacht had taken over the Kaiser Wilhelm Institute of Physics. A military attaché in Stockholm reported, “A tale has again reached me that the Germans are well under way with the manufacture of an uranium bomb of enormous power, which will blast everything, and through the power of one bomb a whole town can be leveled.” Other reports chronicled a mysterious September 1941 meeting where Werner Heisenberg admitted to Niels Bohr, who was living in Nazi-occupied Denmark, that a bomb could be made, “and we’re working on it.”

  The effort to obtain further intelligence was largely the territory of Eric Welsh. From the Griffin the British had some insight into machinations in Berlin. Peierls and Frisch also provided hints of German interest in a bomb by culling lists of German physicists and dissecting any papers they published on atomic research. Again, these added ingredients to the brew, but nothing definitive.

  The best intelligence the British received came through German activity at Vemork. As early as April 1940 Jacques Allier had alerted his British allies to Nazi efforts in uranium research using heavy water from the plant. After the occupation of Paris two months later, the Norwegian supply of 185 kilograms under Joliot-Curie’s care was secreted out of the country aboard a British ship before the Germans could seize it. The twenty-six flasks were hidden in Windsor Castle until the Tube Alloys scientists began their own experiments with the material.

  The continued German focus on heavy water into 1942 was of even greater importance because of a newly discovered element called plutonium. The British were centering their efforts on isotope separation to produce enough pure U-235 for their bomb. But British and American scientists knew this was not the only path toward an explosive. In mid-1940, before the curtain of censorship fell completely, a widely published paper in the Physical Review revealed that when uranium (atomic number 92) is bombarded by neutrons, some split the rare isotope U-235 nuclei but others are absorbed by the much more prevalent U-238 nuclei, transmuting it into the isotope U-239. This unstable isotope decayed by what was called beta emission, which had the effect of increasing the number of protons in the nucleus by one while reducing the number of neutrons by the same amount. This new element, neptunium (atomic number 93), readily decayed once again, creating yet another element, but a stable one: plutonium (atomic number 94).

  As further Allied experiments showed, but now in classified reports, plutonium was fissile, similar to U-235, and could be used as explosive material. However, unlike U-235, plutonium was chemically different from uranium, and thus the two were more easily—and much more cost-effectively—separated. If one managed to engineer a self-sustaining reactor with uranium and a moderator, it would breed enough plutonium that could then be extracted to help build
a bomb. This kind of reactor, Allied physicists theorized, required between three and six tons of heavy water. Through Leif Tronstad, the British knew the Germans were attempting to produce similarly large quantities of heavy water at Vemork.

  At the April 23 Tube Alloys meeting, Akers and his group of scientists discussed the findings of a new SOE source in Norway (a quick-working Skinnarland). According to his coded messages, heavy water production was up to 120 kilograms a month—and increasing. Something, the men at Old Queen Street decided, must be done, and soon. In the minutes of their meeting sent to Churchill’s War Cabinet, they stated, “Since recent experiments have confirmed that element 94 would be as good as U-235 for military purposes, and since this element is best prepared in systems involving the use of heavy water, the Committee recommends that an attempt should, if possible, be made to stop the Norsk Hydro production.” If Vemork had not been a significant target before, it was definitely one now.

  In the weeks that followed, Tronstad suddenly found himself preoccupied with heavy water. On May 1 Wilson sent him a note, asking him to determine where and to whom in Germany Norsk Hydro delivered its supply from Vemork. The same day, he consulted with Akers on the construction of a British heavy water plant. Soon after, he sat down again with Eric Welsh, who wanted him to set up a spy network, both inside and outside Vemork.

  Skinnarland was already providing good intelligence, but it simply wasn’t enough. The Tube Alloys Committee speculated that the Nazis were pursuing a reactor to produce plutonium, a sure road to a weapon, and everything must be known about their activities. Germany was largely closed to intelligence work, but Nazi scientists traveled to Vemork, Oslo, and Stockholm—places where Tronstad had close contacts.

  On May 11 Tronstad wrote two letters, the urgency in his tone clear. The first was to “the Master”: Jomar Brun. Tronstad requested detailed sketches, diagrams, and photographs of the Vemork plant, as well as production figures—anything Brun could discover about the German use of “our juice,” and the specific address where it was sent “so we can give our regards to the people there.” Tronstad wrote: “You can take this as your war effort! It must be pursued with all means.” He signed the letter Mikkel, “the Fox,” his new alias on coming to Britain.

  Tronstad addressed his second to Harald Wergeland, his former student and now a University of Oslo professor. Wergeland had studied under Heisenberg and was close to several other German scientists. Addressing him as “My Dear Young Friend,” Tronstad wrote, in thinly veiled code, “We must know if the Germans have managed to tame the very smallest creatures.” He wanted to know everything Wergeland had learned from his recently reported trip to meet with Niels Bohr. Tronstad instructed him to insinuate himself into the Nasjonal Samling Party, then to attempt a research trip to Germany to “soak up everything possible as quickly as possible.”

  When these letters were brought to Welsh, Tronstad demanded that SIS and the SOE be sure to keep strictly separate communication lines with Skinnarland and with Brun at Vemork. No connection between the two men must be suspected. They did not want another atrocity like the one that had recently happened at Telavåg.

  Almost a month before, the two British services had both used the coastal island village southwest of Bergen as an entry point for their operations. On April 17, two Kompani Linge men arrived by boat into Telavåg to organize resistance groups and conduct sabotage operations. The Gestapo was already on alert after some SIS agents had been seen in the area days before. Some loose talk and gifts of British flour gave away the presence of the Linge men. They were cornered in a house, and a shootout followed. One of them died, the other was captured, and a Nazi SS officer was killed. Reichskommissar Terboven was incensed at the brazen action and by the discovery of arms depots in the village. Norway was under his control, and he would see that this much was clear to all its people by making an example of Telavåg.

  He ordered the village razed and personally watched it happen: every house and building burned down, every boat in the harbor sunk, every animal killed, and the entire community—men, women, and children alike—sent to various concentration camps. Terboven also had eighteen citizens who were caught trying to escape executed by firing squad. He was dutifully following Goebbels’s recommendation: “If they can not learn to love us, they should at least fear us.”

  Tronstad feared the same would happen to those he had tasked with spying for him. Such thoughts weighed heavily on him, especially since he slept safely at night in a house beside the expansive Hampstead Heath while some of his countrymen were in constant jeopardy.

  If Lillian Syverstad was stopped by a German soldier, and there were always German soldiers patrolling Rjukan, she would simply say that she was on her way to visit her sister, Maggen, who was married to the assistant dam-keeper Torstein Skinnarland up on Lake Møs. Lillian, a pretty eighteen-year-old, worked in the town’s bookshop, and she could smile and charm her way out of most situations. That particular June day, she carried a folded note, which had been passed to her by a friend in town. It was likely from her brother Gunnar, a laboratory assistant at Vemork, but Lillian never knew—and never looked to see—what the messages were. It was for the best. She could not confess what she did not know. Once she reached the dam, she made sure nobody was watching, then left the note behind a simple round stone. Soon afterward, Lillian’s childhood friend, Einar Skinnarland, retrieved the note, and yet another scrap of intelligence on Vemork was collected.

  On the night of his parachute drop into Norway, a strong northwest wind had blown Skinnarland into a rocky hillside. He hit the ground hard, his spine compressing like an accordion. When he stood and gathered his parachute, he felt something pop in his lower back, but there was nothing to be done about it. He quickly found the small package that had been sent out after him, but the tube container with the weapons was nowhere in sight. Finding it in the dark was hopeless.

  From the silhouette of Mount Gausta, Skinnarland reckoned he was at least ten miles northwest of Lake Møs. His back shooting with pain, his knee still tender, he made his way through the craggy mountains toward home. He arrived just before dawn. Only his brother Torstein knew where he had been. The rest of his family greeted him warmly and asked how his long hunting trip had gone. He begged off any questions about his stiff back, and there was little time for a reunion.

  Skinnarland set off on skis to meet his friend and confidant Olav Skogen, operating out of a mountain lodge halfway to Rjukan. The local Milorg leader, with a shock of dark, curly hair swept high over his broad forehead, guessed from the outset where Skinnarland had been. Hearing about the drop, Skogen stressed the need to find the container of weapons he’d been supplied as quickly as possible. The two set off for the drop site but found nothing. The container was likely hidden in a drift of snow and would never be recovered.

  Skinnarland returned to his job building a dam at Kalhovd, eighteen miles north of Lake Møs. There was little time to see Gudveig, who lived in Bergen, but now and again he sent her letters, saying nothing of his undercover work. He began gathering intelligence on Vemork, partly through his own reconnaissance but mostly through his contacts inside the plant.

  Skinnarland did not know it, but Jomar Brun was also providing a wealth of information about Vemork to London. On October 3, 1941, Paul Harteck and another German scientist had traveled to Rjukan with Consul Erhard Schöpke. A Nazi zealot with the medal-bedecked uniform to match, Schöpke was responsible for exploiting the country’s industry for the Third Reich as a member of the Wehrwirtschaftsstab Norwegen (War Economy Staff for Norway). Accompanying them was Bjarne Eriksen; Norsk Hydro’s former lawyer had replaced Axel Aubert as director general on his retirement. Despite the company’s earlier support of the Allies, Eriksen had essentially taken the position since the occupation that the firm’s survival was more important than patriotism—or, as some of its workers said more bluntly, “Long live Hydro . . . To hell with Norway.”

  After Brun gave a tour of t
he heavy water plant, the men gathered in the stately administration headquarters in Rjukan. They enjoyed a nice dinner and then, around a warm fire, smoking cigars and sipping whiskey, Schöpke got to the business at hand. Production numbers were off and something needed to be done. In the twenty months since the Germans invaded, Vemork had delivered 390 kilograms of heavy water, despite German orders of 1,500 kilograms a year. Not only was Norsk Hydro falling far short of the first target, but the company needed to more than triple production, to 5,000 kilograms a year.

  Then Harteck spoke. There were two ways to increase production to such a level. First, they could expand the electrolysis plant as it now operated, adding more electrolyzers to the initial cascade and doubling the size of the high-concentration plant. Second, they could test and institute a new technology (catalytic exchange) that held out the promise of not wasting the deuterium burned off as gas during electrolysis. In the end, they decided to do both.

  Brun was instructed to develop a plan to institute these ideas. Unwilling to help, and still unsure of why the heavy water was needed, Brun dragged his feet. In the months before, he had actively slowed production by contaminating the high-concentration cells with cod-liver oil, making the heavy water foam. He could not continue interrupting production this way without exposure, however. In January 1942 he was ordered to Berlin. At the Army Ordnance Department in Hardenbergstraße 10, he endured more meetings and more demands for increased production, chiefly from one Dr. Kurt Diebner. When Brun asked Diebner what was the purpose of such quantities of heavy water, Diebner answered they would be sent to the “quinine factory” to make a refreshing tonic. Brun was not amused.