0
23
Mary, Queen of Scots used 'spiral locking' technique to preserve secrecy of last letter before her execution
An example of letterlocking -- where people doubled letters as envelopes to ensure the security of a document -- the fallen monarch used a spiral locking process to seal a message that was "a last will and testament and a bid for martyrdom.
Mary was shrouded in political controversy during her lifetime. She was next in line to the throne after Henry VIII's children, and was targeted by conspirators under the reign of her English cousin, Elizabeth I. Mary was interned for 19 years, after which she was executed at the age of 44.