Reporter | Xu Yuedong
According to the " Guardian ", recently, the "Unlocking History Team" of King's College London , MIT and The "Unlocking History Team" of the University of Glasgow discovered the content of the last letter written by Queen Mary before being executed. The letter used the exquisite "letterlocking" technology to ensure that the content of the letter was not discovered.
Mary Stuart (1542-1587), also known as Mary I. She is the Queen of Scotland and Queen of France, and is known for her beauty. In 1567, her throne was deposed and was imprisoned by Queen Elizabeth I for eighteen years from the following year. She was finally executed for the crime of attempting to murder Elizabeth I at the age of 45.
Researchers found that on February 8, 1587, before her execution, she wrote a letter to the King of France Henry III in , and Mary wrote that she "had been told of her verdict that I would be executed like a criminal at 8 am. I asked them to give me paper so that I could make a will, and I had never been able to recover anything that would work for me, and I could not even write my will freely. I also could not decide to allow my body to be shipped to your kingdom as I wish. There, I had the honor to become Queen of France and become your sister and ally." The letter is now hidden in the National Library of Scotland.

Queen of Mary in Scotland
"Unlock History Team" found that Mary used a clever folding technique to seal the letter. If this letter is tampered with, the recipient will definitely find it. This "Unlock History Group" has been exploring the history of "envelopes". Before the envelope was invented, the letters were cleverly folded into envelopes by the ancients.
Earlier this year, the "Unlock History Team" successfully unopened an envelope that was not untie in 1697. They used X-rays to view the internal information of the letter and created 3D images. As part of the study, they looked at nearly 250,000 ancient letters and discovered a folding technology called "spiral lock". The "locking letter" technology used by Queen Mary of Scotland belongs to this complex "spiral locking" technology.
The research team believes that "'spiral lock' is one of the most eye-catching letter sealing technologies... This is Mary's last letter," "The content of this letter is very touching. It is not only a letter - a document for the far-reaching recipient to read - but also the final will." "The letter must be folded and hidden. After writing the last message, Mary is ready to deliver it to others after she passes the seal of the 'letter lock' technology."
The Unlock History Group also believes that the process of exploring the "letter lock" technology is very challenging, because the letters "letter lock" are to be "destroyed" by the recipient. Making a "spiral lock" requires more than thirty steps, and sometimes adhesive is required. "This is a very complex technology, which requires time, patience and superb skills: as long as there is an error, the locking mechanism cannot be completed, and you have to rewrite the letter."

The last letter from Queen Mary of Scotland, the picture is from the National Library of Scotland
When the recipient receives the letter sealed with the "letter lock" technology, he needs to tear the letter open to read the content. When tearing a letter, multiple parts of the letter will break, so once this letter is opened, it will not be possible to recover again. Therefore, if someone wants to open the letter to tamper with it, the recipient can easily discover it.
Medtech scholar Jana Dambrogio believes that the letter was written by Mary in prison, and we have reason to believe it was locked by herself. This letter has great historical significance for Scotland. Moreover, Mary used the most complex "letter lock" technology, which is a variant of the "letter lock" technology. It can be inferred that Mary can use extremely limited tools in prison.

A type of "lock letter" technology, picture from Wikipedia
Scholar Daniel Starza Smith of King's College London said, "The envelope is one of the most important communication technologies in the world, but its history has just been dug."In the six hundred years before the invention of modern glue-coated envelopes in the 19th century, most ancient letters used some kind of "letter locking" technology. It is as important as today's computer programming. Research on the ‘locking letter’ technology helps us to provide important help to study historical figures. ”
reference link: https://www.theguardian.com/books/2021/dec/10/mary-queen-of-scots-locked-final-letter-using-paper-folding-research-find-final-final-final-fining-paper-folding-research-finds, https://en.wikipedia.org/wiki/Letterlocking
Reporter | Xu Yuedong
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