Floating on ice

A friend emailed today to tell me that Giles Foden’s new book Turbulence contained a sequence in which the central character made a voyage on a boat made of Pykrete. Turbulence is a novel, but Pykrete was entirely real. It was a frozen mixture of water and wood pulp that was central to the secret war project, codenamed Habbakuk, that occupied some of the best scientific brains in Britain throughout most of 1943.

Pykrete was named after Geoffrey Pyke, an extraordinary entrepreneur and inventor who somehow gained the ear of Louis Mountbatten, then Chief of Combined Operations. In the autumn of 1942, having been despatched to the US, Pyke wrote a 250-page memo to propose a fantastic project: the construction of a fleet of vast aircraft carriers out of ice. His fellow scientific advisor, the physicist and Communist John Desmond  Bernal, whittled this down to two pages that sounded half sensible. In remarkably short order Churchill gave the project his approval, and Bernal hired the young Cambridge crystallographer and Austrian refugee Max Perutz to work on ways of making ice stronger.

Perutz adopted a method discovered by his fellow Austrian Hermann Mark, then working at Brooklyn Polytechnic in New York. By mixing wood pulp or other fibrous material into water as it was freezing, one could make ice that was resistant to cracking even if assaulted by a bullet fired from a pistol. Demonstrations of this impressive material kept the top brass fascinated, but no one properly explored the seaworthiness of Pyke’s proposed vessels, or the costs of building them, until the Americans joined the project and quickly cancelled it.

The story of Habbakuk and Pykrete is an extraordinary example of the faith Britain’s wartime leaders placed in their ‘boffins’ – mostly, it has to be said, with justification. Radar and the code-breaking computer Colossus are two of the triumphant successes that resulted. Foden’s novel is based on the true story of the attempts to forecast the weather accurately for the D-Day landings, another success.

I ran across Habbakuk – in the form of a groaning table of wartime files in the British National Archives – in the course of researching my biography of Perutz, which Foden reviewed for the Guardian.

This is the first post in a blog in which I hope to comment on scientific themes as they crop up in contemporary culture, and reflect on science in our history. Hope you enjoy it.