# Researchers read sealed 17th-century letter without opening it



## mosaix (Mar 2, 2021)

Researchers read sealed 17th century letter without opening it
					

‘Virtual unfolding’ is hailed a breakthrough in the study of historic documents as unopened letter from 1697 is read for the first time using X-ray technology




					www.theguardian.com
				




I_n a world first for the study of historic documents, an unopened letter written in 1697 has been read by researchers without breaking the seal.

The letter, dated 31 July 1697 and sent from French merchant Jacques Sennacques in Lille to his cousin Pierre Le Pers in The Hague, had been closed using “letterlocking”, a process in which the letter is folded to become its own envelope, in effect locking it to keep it private. It is part of a collection of some 2,600 undelivered letters sent from all over Europe to The Hague between 1689 and 1706, 600 of which have never been opened.

The international team of researchers from universities including MIT, King’s College London, Queen Mary University London, Utrecht and Leiden, worked with X-ray microtomography scans of the letter, which use X-rays to see inside the document, slice by slice, and create a 3D image. They applied computational flattening algorithms to the scans to enable them to virtually unfold the letter without ever opening it, and discovered that Sennacques had been asking his cousin for a certified copy of a death notice of one Daniel Le Pers._

'Computational flattening algorithms' - incredible.


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## Mouse (Mar 2, 2021)

I've read the whole thing and couldn't really find a reason (not a proper reason) why they couldn't have just opened it. Just open it, for goodness sake. I mean, amazing tech, but just open the bloody thing. I dunno why, but that really irritates me!


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## Vladd67 (Mar 2, 2021)

Mouse said:


> I've read the whole thing and couldn't really find a reason (not a proper reason) why they couldn't have just opened it. Just open it, for goodness sake. I mean, amazing tech, but just open the bloody thing. I dunno why, but that really irritates me!


Perhaps after all this time folded in this way the letter has become brittle and opening it would damage it?


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## .matthew. (Mar 2, 2021)

I'm having a hard time believing this is the first time they've tried this. Haven't they been x-raying painting and old documents for decades now? I mean sure, unopened letter, maybe a first... but hardly newsworthy tech


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## Bick (Mar 2, 2021)

Mouse said:


> I've read the whole thing and couldn't really find a reason (not a proper reason) why they couldn't have just opened it. Just open it, for goodness sake. I mean, amazing tech, but just open the bloody thing. I dunno why, but that really irritates me!


Completely agree!


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## Brian G Turner (Mar 3, 2021)

They're using similar on burned scrolls from Pompeii, which are too brittle to try and open, yet might still be machine readable in this manner. Looking forward to reading more results on that work.


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## .matthew. (Mar 3, 2021)

Brian G Turner said:


> Looking forward to reading more results on that work.



2 loaves of bread
1 bag of olives
4 bags of pasta
1 bucket of milk
1 reusable lambskin prophylactic
1/2 block of cheese
1 anti-soot dust mask
1 ticket out of town
1 Cadbury's chocolate orange


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## .matthew. (Mar 4, 2021)

.matthew. said:


> 1 Cadbury's chocolate orange



I was lying in bed last night when the thought erupted in my mind... _Cadbury's _don't make _Terry's_ chocolate oranges...


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## Brian G Turner (Mar 7, 2021)

Vladd67 said:


> Perhaps after all this time folded in this way the letter has become brittle and opening it would damage it?



That's what's reported:








						Secrets of sealed 17th century letters revealed by dental X-ray scanners
					

In a world first, an international team of researchers has read an unopened letter from Renaissance Europe—without breaking its seal or damaging it in any way.




					phys.org
				






> Until now these letterpackets could only be studied and read by cutting them open, often damaging the historical documents.


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## Parson (Mar 8, 2021)

.matthew. said:


> 2 loaves of bread
> 1 bag of olives
> 4 bags of pasta
> 1 bucket of milk
> ...


Reminds me of _A Canticle for Leibowitz. _Perhaps we have the beginnings of a new sacred text.


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## hitmouse (Mar 8, 2021)

Interesting thing on this in The Economist. Elaborate folding of letters, for security, was a big thing at the time these were written. Letters could not be opened and refolded without showing signs of tampering. Some had internal seals as an addedlayer of assurance.  The folding techniques are poorly understood because most of the surviving letters were opened at the time. The article suggests that the folding, rather than the written contents, is the main archaeological prize here which partly explains why virtual unfolding is useful. 

And just to show off, of course.


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