Mary, Queen of Scots, sealed her closing missive with an intricate spiral letterlock

On the eve of her execution for treason in February 1587, Mary, Queen of Scots, penned a letter to King Henri III of France and secured it with a paper lock that featured an intricate spiral mechanism. So-called “letterlocking” was a standard observe to guard non-public letters from prying eyes, however this spiral lock is especially ingenious and delicate as a result of it incorporates a built-in self-destruct function, in keeping with a brand new paper printed within the Digital British Library Journal.

The authors are an interdisciplinary group of researchers working underneath the umbrella of the Unlocking Historical past Analysis Group. On this paper, they describe a dozen examples of a spiral lock in letters dated between 1568 and 1638, together with one from Mary’s former mother-in-law, Catherine de Medici, in addition to her arch-rival, Elizabeth I, who signed Mary’s demise warrant.

As we reported beforehand, co-author Jana Dambrogio, a conservator at MIT Libraries, coined the time period “letterlocking” after discovering such letters whereas a fellow on the Vatican Secret Archives in 2000. The Vatican letters dated again to the fifteenth and sixteenth centuries, and so they featured unusual slits and corners that had been sliced off. Dambrogio realized that the letters had initially been folded in an ingenious method, basically “locked” by inserting a slice of the paper right into a slit, then sealing it with wax. It could not have been potential to open the letter with out ripping that slice of paper—proof that the letter had been tampered with.

Dambrogio has been finding out the observe of letterlocking ever since, typically creating her personal fashions to showcase totally different methods, ultimately forming the Unlocking Historical past Analysis Group. The observe dates again to the thirteenth century—at the very least in Western historical past—and there are various totally different folding and locking methods that emerged over the centuries. “It is not like individuals might simply go to a store and purchase an envelope,” Dambrogio’s co-author from King’s Faculty London, Daniel Starza Smith, instructed Ars.

Queen Elizabeth I, Machiavelli, Galileo Galilei, and Marie Antoinette are among the many well-known personages identified to have employed letterlocking for his or her correspondence. There are tons of of letterlocking methods: for instance, “butterfly locks,” a easy triangular fold-and-tuck, and an ingenious technique generally known as the “dagger-trap,” which includes a booby-trap disguised as one other, less complicated sort of letter lock. And naturally, there’s the intricate spiral lock that Mary, Queen of Scots, used for her closing missive.

Earlier this 12 months, Dambrogio’s group was ready to make use of X-ray tomography to nearly “unlock” a letter written in 1697 by a person named Jacques Sennacque. Their evaluation revealed its contents for the primary time, proper right down to the watermark within the form of a fowl, as described in a paper printed within the journal Nature Communications. That letter was a part of the Brienne Assortment, a group of two,600 “locked” letters—600 of which had by no means been opened—present in a Seventeenth-century trunk of undelivered letters preserved within the postal museum at The Hague, the Netherlands.

The unopened letters within the Brienne Assortment meant that rather more materials proof (crease marks and wax seals, for example) a few given letter’s inner safety was preserved, particularly proof of tucks and layer order, which usually go away no materials hint. In contrast, the letters examined on this newest paper have all been opened, presenting a unique sort of problem for the researchers of their ongoing quest to reverse-engineer the creation of letterlocks.

A excessive share of the fabric proof for the letterlocks is often destroyed by opening the letter, and the spiral lock is designed to destroy not simply the lock, but in addition typically parts of the particular letter as an added safety measure, in keeping with the authors. Subsequent dealing with by students and conservationists also can obscure proof of using a letterlock. Such gadgets are typically sure into letter books or saved after flattening and humidification, and the remnants of wax seals could be saved individually, discarded, or reattached incorrectly.