by Per F Dahl, Institute of Physics Publishing 0 7503 0633 5 (£35).
Per Dahl is a physicist who has made significant contributions to the design and development of superconducting magnets for particle accelerators. He also has a burning interest in the history of modern science. It is not surprising that he has already written a book on the history of superconductivity (1992 Superconductivity: Its Historical Roots and Development from Mercury to the Ceramic Oxides American Institute of Physics).
Continuing on his history beat, Dahl is also the author of The Flash of the Cathode Rays (1997 Institute of Physics Publishing). Advertised as a history of J J Thomson’s electron, it is in fact a careful documentation (with nearly 100 pages of footnotes) of many other developments in fundamental physics, from time immemorial up to the early 1930s, where the book stops. Dahl is also the son of CERN pioneer and colourful Norwegian scientific personality Odd Dahl (18981994).
In Dahl’s new book, heavy water is the hero of a saga that unfolds where Dahl’s previous book left off, and it continues up to 1945. In the early 1940s, just after the discovery of nuclear fission, many people were convinced that heavy water was the key to new nuclear physics progress. With little of the substance around, attention was soon focused on Norway, which had an abundance of hydroelectric power for manufacturing processes.
With the outbreak of the Second World War, both sides were eager to get a supply of heavy water and to prevent it from falling into enemy hands. In 1940 the French cornered 185 kg of Norwegian deuterium, which was spirited to Paris via the UK in an elaborately planned operation. With the invasion of France, the heavy water had to be smuggled out again. It eventually found a temporary home in Windsor Castle, England, before being used in wartime Cambridge and then in Montreal, with Lew Kowarski and Hans von Halban playing leading roles.
In 1942 and 1943, allied commando raids and air strikes on the heavy-water plant in occupied Norway attempted to put the factory out of business. This culminated in the famous 1944 Norwegian Resistance operation, which intercepted a ferry carrying tons of deuterium-rich material en route to Germany and sank it in Lake Tinnsjø. Eighteen lives were lost. In 1965 the episode was made into a film called The Heroes of Telemark, which starred Kirk Douglas.
Dahl manages to combine scientific accuracy with a compelling storyline that keeps the pages turning. Like his cathode-ray book, the volume is meticulously researched, particularly with regards to Norway (although this time the footnotes have been abridged to a mere 57 pages). It is a remarkable read.
