A rare WWII gadgets catalogue from Britain's secretive MI9 department is coming to auction.
The remarkable 76-page book, which details a range of ingenious contraptions that could be used by would-be escapees from prisoner of war camps, will sell at Bonhams' Gentleman's Library auction in London on January 30.
It was one of a limited number of copies given to American intelligence officers in 1942, following their visit to Britain to study MI9's modus operandi.
Formed in 1939, MI9 aided resistance movements in enemy territory.
It also helped several British prisoners of war escape, by sending them equipment designed as everyday items.
Named Per Ardua Libertas, Latin for Freedom through Hard Work, the catalogue includes compasses contained within gold teeth and coat buttons, cameras in the form of cigarette lighters, and maps printed on silk so that they could be disguised as handkerchiefs and would not rustle.
Lionel Willis, Bonhams' specialist, explained the likely attraction of the piece with bidders.
"Very few of these catalogues are known to have survived and the remaining copies form rare pieces of secret service history," he said.
"They give a fascinating insight into the ingenuity employed to assist the war effort."
The book has just an £800 ($1,293) estimate, one that we think it will easily surpass, such is its fascinating content.
Second world war memorabilia consistently achieves strong results at auction. A US naval dispatch declaring the end of WWII sold for $20,500 at a Pennsylvania sale in August.
The Gentleman's Library auction, now in its 12th year, features a range of items that would have amused a Victorian or Edwardian gentleman, including globes and fossils.