alternative [explanation]. When we finish tomorrow or the day after I will send you a copy of the manuscript… The whole thing is not very well suited for
Hahn mailed the letter to Stockholm. He did not yet know about Meitner's Kungalv vacation.
Leo Szilard's work at the University of Rochester confirmed that no neutrons came out when indium was irradiated. On December 21, as Hahn and Meitner exchanged their excited letters, Szilard advised the British Admiralty by letter:
Further experiments… have definitely cleared up the anomalies which I have observed in 1936… In view of this new work it does not now seem necessary to maintain [my] patent… nor would the waiving of the secrecy of this patent serve any useful purpose. I beg therefore to suggest that the patent be withdrawn altogether.
Szilard's faith in the possibility of a chain reaction, as he said later, had “just about reached the vanishing point.”
Hahn and Strassmann had originally titled their paper “On the radium isotopes produced by the neutron bombardment of uranium and their behavior.” With their new data they realized “radium” would no longer do. They considered changing “radium” to “barium” throughout the paper. But most of it had been written before the lanthanum experiment firmed their convictions. They would have had to rewrite from beginning to end, “especially,” says Hahn in retrospect, “since in view of this result its major portion was not especially interesting any more.” Christmas and the journal deadline were upon them and they had no time. They decided to jury-rig what was on hand. The results would be no less effective for being inelegant. They substituted the noncommittal phrase “alkaline-earth metals” for “radium isotopes” in the title — both barium and radium are alkaline-earth metals, as are beryllium, magnesium, calcium and strontium. They went through the draft putting equivocal quotation marks around their many references to radium and actinium. Then they attached seven cautious paragraphs at the end.
“Now we still have to discuss some newer experiments,” this final section began, “which we publish rather hesitantly due to their peculiar results.” They then summarized their series of experiments:
We wanted to identify beyond any doubt the chemical properties of the parent members of the radioactive series which were separated with the barium and which have been designated as “radium isotopes.” We have carried out fractional crystallizations and fractional precipitations, a method which is well-known for concentrating (or diluting) radium in barium salt solutions…
When we made appropriate tests with radioactive barium samples which were free of any later decay products,
They discussed actinium then, distinguished their work from that of Curie and Savitch and pointed out that all so-called transuranics would have to be reexamined. Not quite prepared to usurp the prerogative of the physicists, they closed on a tentative note:
As chemists we really ought to revise the decay scheme given above and insert the symbols Ba, La, Ce [cerium], in place of Ra, Ac, Th [thorium]. However as “nuclear chemists,” working very close to the field of physics, we cannot bring ourselves yet to take such a drastic step which goes against all previous laws of nuclear physics. There could perhaps be a series of unusual coincidences which has given us false indications.
Promising further experiments, they prepared to release their news to the world. Hahn mailed the paper and then felt the whole thing to be so improbable “that I wished I could get the document back out of the mail box”; or Paul Rosbaud came around to the KWI the same evening to pick it up. Both stories survive Hahn's later recollection. Since Rosbaud knew the paper's importance and dated its receipt December 22, 1938, he probably picked it up. But Hahn also visited the mailbox that night, to send a carbon copy of the seminal paper to Lise Meitner in Stockholm. His misgivings at publishing without her — or some dawning glimmer of the fateful consequences that might follow his discovery — may have accounted for his remembered apprehension.
The Swedish village of Kungalv — the name means King's River — is located some ten miles above the dominant western harbor city of Goteborg and six miles inland from the Kattegat coast. The river, now called North River, descends from Lake Vanern, the largest freshwater lake in Western Europe; at Kungalv it has cut a sheer granite southward-facing bluff, the precipice of Fontin, 335 feet high. The modern village is built along a single cobblestone lane on the narrow talus between the bluff and the river, its back to the wall.
As Norwegian Kongahalla the village was founded at a less constricted place downstream around a.d. 800. But an island hill rises from the river at Kungalv and is thus guarded by a natural moat, a defensive geography which the precipice of Fontin reinforces. In 1308, to mark the border there between Norway and Sweden, the Norwegians began to build on that island hill a monumental granite fortress, Bonus' Faste (i.e., King Bohus' Fort), sod-ridged block walls mazing inward and upward to a cylindrical tower of thick stone with a conical roof that dominates the entire coastal valley. An accident of placement of three of the deep windows that penetrate the tower — two open above, one centered below — transforms it into a face staring with hollow eyes toward the Fontin bluff. To soften the grim-ness of that face the people of the valley named the tower
The village was ordered moved upriver onto the island in 1612. The Danes ruled Norway from the fifteenth century to the early nineteenth century; they ceded the Kungalv region, Bohuslan, to Sweden by the Treaty of Roskilde in 1658. Fire in 1676 burned the island village and its burghers shifted for safety to the narrow shore. They laid out their lane and strip of houses extending west and east from a cobblestone marketplace where the talus widened to make room. Despite its fortress Kungalv is peaceful, especially in winter with the river frozen and a depth of clean snow on the ground. Its snug wooden houses, painted pastel, enclose rooms cozy with ships' chests and china cabinets and lace curtains, warmed by corner fireplaces faced with decorative tile, aromatic with coffee and baking. Eva von Bahr-Bergius and her husband Niklas built a house there in 1927, larger than most Kungalv houses but constructed in the same style. In 1938 Lise Meitner was alone in Stockholm. Otto Frisch was alone in Copenhagen, his mother, Meitner's sister, beyond reach in Vienna, his father incarcerated at Dachau, a victim of
Meitner left Stockholm Friday morning, two days before Christmas. Frisch took the train ferry across from Denmark. His aunt arrived before him and registered at a quiet inn on Vastra gatan, West Street, where they both would stay, a pale green building much like its modest neighbors but with a cafe on the ground floor. It faced a shadowed strip of garden north across the lane; above the stunted garden trees the dark bluff loomed. The other way, behind the inn, the flat, snow-covered flood plain of the river extended into open woods. The Bergiuses' house was a short walk eastward past the marketplace and the white church. Tired from travel, Frisch and Meitner met only briefly in the evening when Frisch came in.
In Copenhagen that winter he had been studying the magnetic behavior of neutrons. To further his work he needed a strong, uniform magnetic field, and on his way to Kungalv he had sketched out a large magnet he meant to design and build. He came downstairs on the morning before Christmas prepared to interest his aunt in his plans. She was already at breakfast and had no intention of discussing magnets: she had brought Hahn's December 19 letter downstairs with her and insisted Frisch read it. He did. “Barium,” he told her, “I don't believe it. There's some mistake.” He tried to change the subject to his magnet; she changed it back to barium. “Finally,” says Meitner, “… we both became absorbed in my problem.” They decided to go for a walk to see what they could puzzle out.
Frisch had brought cross-country skis and wanted to use them. He was concerned that his aunt would be unable to keep up. She could walk as fast as he could ski on level ground, she told him. She could and did. He fetched his skis and they went out, probably eastward to the Kungalv marketplace, which gave onto the flood plain
