Removal of French Heavy Water Stocks and nuclear scientists from France to UK in June 1940

It seems that just before surrender of France in June 1940 , British Department of Scientific and Industrial Research took over and removed all French heavy water stocks plus millions of dollars worth of diamonds from Antwerp Diamond Board , some heavy machinery for arms production left behind in port and all top French nuclear scientists plus their families in a top secret operation from Bordeux harbour and to UK out of Germans reach under leadership of department liason of Charles Howards 20th Earl oF Suffolk.

from wikipedia :

As Liaison Officer for the British Department of Scientific and Industrial Research during the Second World War , the Earl of Suffolk Charles Howard and his colleague Major A. V. Golding were posted to Paris. They, and their private secretaries, Eileen Beryl Morden and Marguerite Nicolle, left Paris on 10 June 1940 due to the impending Fall of France

From there they made their way to Bordeaux, where British Embassy representatives introduced them to the master of the British tramp ship SS Broompark which was one of many standing by to carry refugees to safety. They embarked thirty-three eminent scientists, with their families. Two more scientists, Lew Kowarski and Hans Halban arrived with entire heavy water stocks of France (26 cans containing 185 kilograms (408 lb) of heavy water )

Then the managing director of the Antwerp Diamond Bank, Paul Timbal, joined, with $10 million worth of gem diamonds. They discovered six hundred tons of machine tools for war material production in wagons on the quay, which were also loaded onboard under command of Earl of Suffolk.

The SS Broompark carried all of them safely to Falmouth UK on 19th June (48 hours before French surrender), from where a special train took her passengers and cargo to London. The diamonds were placed in the vaults of the Diamond Corporation and most of the heavy water was sent to Windsor Castle , where it was stored alongside the Crown Jewels until needed.

Howard’s approach to his missions earned him the nickname “Mad Jack” or “Wild Jack”. Herbert Morrison , Minister of Supply, later described him as “one of the most remarkable young men employed by the Government on dangerous missions.” Morrison told the House of Commons, when in Secret Session, that "A considerable service has been rendered to the Allied cause by the safe arrival of this shipload.

SS Broompark


Charles Howard , Earl of Suffolk (who was killed during a bomb disposal mission in May 1941)


Maybe more detail on heavy water stocks here:

"French research considered production of 239Pu using reactors moderated by both heavy water and graphite. Preliminary French research indicated that the graphite which was then available commercially was not pure enough to serve the purpose, and that heavy water would be required. The German research community had reached a similar conclusion and in January 1940 had procured additional heavy water from Vemork. The German firm IG Farben, which was a partial owner of Norsk Hydro, had ordered 100 kg (220 lb)/month; Norsk Hydro’s maximum production rate was then limited to 10 kg (22 lb)/month.[1]

In 1940, the “Deuxième Bureau” (French military intelligence) directed three French agents, Captain Muller and Lieutenants Mossé and Knall-Demars, to remove the world’s extant supply, 185 kg (408 lb) of heavy water from the Vemork plant in then-neutral Norway. The Norsk Hydro General Director, Axel Aubert, agreed to lend the heavy water to France for the duration of the war, observing that if Germany won the war he was likely to be shot. Transportation was difficult as German Military Intelligence (the Abwehr ) maintained a presence in Norway and had been alerted of ongoing French activities in Norway (although they had not been specifically warned about heavy water). Had they become aware of the shipment, they might have attempted to intercept it. The French transported it secretly to Oslo, to Perth in Scotland, and then to France.[1]

When France was invaded the French nuclear scientist Frédéric Joliot-Curie took charge of the material, hiding it first in a Banque de France vault and then in a prison. Joliot-Curie then moved it to Bordeaux, where it, plus research papers and most of the scientists (Joliot-Curie remained in France) boarded the British tramp steamer Broompark , which was one of the many merchant ships involved in saving over 200,000 troops and civilians in the three weeks after the evacuation at Dunkirk.[11] The ship already had industrial diamonds, machinery and a number of British evacuees aboard. SS Broompark delivered its passengers and cargo, together with all of the free supply of heavy water, to Falmouth on 21 June. The award of an OBE to Captain Paulsen was recorded in the London Gazette of 4 February 1941. Crucial to the success of the mission was the role played by Charles Howard, 20th Earl of Suffolk.

Although the ready inventory of heavy water was removed, the plant remained capable of producing heavy water. In investigations of collaboration launched by Norwegian authorities after the war, Norsk Hydro management’s collaboration with the Germans was considered. General Director Aubert’s cooperation with the French aided the Norsk Hydro case.


Frédéric Joliot-Curie was the husband of Irène Joliot-Curie, the daughter of Pierre and Marie Curie (famous nobel winning scientists for their work on radiation). Both would also win a nobel price for their work on radioactivity.

They would carry heavy water in their car to cross France.

Frédéric Joliot-Curie would send to England two of his jewish collaborators, with all the documentation on what he was working on, Hans Halban and Lew Kowarski. The papers they carried described the outline of a design for a nuclear fission reactor and how to produce plutonium.
They both worked later in Montreal Laboratory in Canada on the Manhattan project during the war.

Frédéric Joliot-Curie would stay in France and refused to help the german scientists that would take over the french labs. He would join the resistance and supervised the making of his own “molotov cocktail”-like invention against german tank to help during the liberation of Paris in 1944.

After the war, he would supervise the construction of the first atomic reactor in France, first activated in 1948.
The Zoe reactor . Using heavy water.

(There is a franco-norwegian movie made in 1948, with Frédéric Joliot-Curie playing his own role )

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