A rare wartime book documenting the ingenious James Bond-style gadgets invented by British 'spooks' to help prisoners of war escape has been discovered.
The 1942 classified catalogue contains the designs for the covert equipment including tiny compasses concealed in gold teeth and coat buttons.
Many of the inventions were the brainchild of Christopher Hutton - a real-life 'Q' from the James Bond movies - who worked for the government's little-known MI9 agency.
Less than 100 of the instruction manuals were printed and given to US intelligence officers who were lagging behind the British in espionage design after entering the war late.
The 76 page book details what the gadgets were and how they were made and concealed in innocuous domestic items.
The gadgets were placed in food parcels and sent to British PoWs in camps like Colditz or the 'Great Escape' prison, Stalag Luft III.
Some of the fascinating gadgets include maps of Germany printed on silk so that they didn't rustle and crammed inside pencils, vinyl records, cigars and pipes.
Another map was hidden under the surface of 54 playing cards that, when pieced together, formed a large map of Germany and Europe.
Small hacksaws were secreted in dart boards while a tiny camera was hidden inside a cigarette lighter and small radio receivers in cigar boxes.
The extremely rare copy of the book called 'Per Ardua Libertas' - Liberty Through Adversity - that has come to light was a dummy version retained by the London printing company.
It is now being sold at auction by a Devon man who inherited it from one of the executives of the company.
The page that contains the playing cards shows a corner of the surface of the Queen of Clubs peeled back to expose part of a map.
The instructions read: "Each pack is one map. 48 cards covered a map. The 4 Aces are a small map of Europe. The Joker is the key. The outside card contains the instructions."
For the compass concealed in a gold tooth, the instructions reads: "Tooth - Gold Fitting made to measure.
"Small medium luminous compass fits in jaws on left and thin gold tube holding message or map slides on the two prongs at the bottom. They are concealed through being in between the cheek and the gum."
Lionel Willis, a specialist at auctioneers Bonhams which is selling the book, said it was an exceptionally rare find.
He said: "The MI9 department was set up in 1939 to aid escapees and resistance fighters.
"They very quickly realised that two things were vital if you were going to escape in a foreign country and they were a map and a compass.
"They produced maps on pieces of silk that could be rolled up and secreted in extremely small spaces inside innocuous domestic items and this books show how they were concealed in things like pencils and cigars.
"Food parcels and rations packs were sent to prisoners of war and every sixth parcel contained some of these inventions that helped them escape.
"The British were way ahead of the US and in 1942, after America had entered the war, the US intelligence service sent a group of people to London to see what we were up to and how we were doing it.
"MI9 produced this book to give to the Americans, probably less than 100 were printed.
"Very few of these catalogues are known to have survived. I believe the Australian War Museum has a copy.
"It gives a fascinating insight into the ingenuity employed to assist the war effort."
As well as PoWs, Allied spies and resistance fighters were also sent the gadgets to help them either escape or outsmart the Nazis
The book is being sold by Bonhams next January with a pre-sale estimate of £800.
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