Left on the floor of a Fleet St pub, Britain's greatest Cold War secret
The notebook contained never before seen details of Britain's top secret code-breaking site Eastcote, which was later to become the Government Communications Headquarters (GCHQ).
Eric Tullett, a Sunday Express journalist, had been passed the explosive information detailing Britain's operation to intercept and decode Soviet signals by Arthur Askew, the Foreign Officer's former head of physical security.
But his extraordinary scoop was lost when he left his notebook on floor of the Old Bell pub, on London's Fleet Street.
At the time the public were in the dark about the Cold War cipher work being carried out at Eastcote. Nor did they know about Bletchley Park, the wartime cryptography site which pioneered the art of using early computer technology to break encrypted messages....