4 ms·
Letterlocking
- deleted 6y ago[deleted]
- gen220 6y agoThere was a cool article on this subject a few weeks ago: https://www.npr.org/2021/03/02/972607811/reading-a-letter-thats-been-sealed-for-more-than-300-years-without-opening-it https://www.npr.org/2021/03/02/972607811/reading-a-letter-th... Basically, opening centuries-old letters that are sealed with this technique is usually a destructive process: you might end up rendering some portions of the letter unreadable. As such, many of these letters have never been opened! They might contain interesting things, but we have no idea. Some researchers figured out a way to "unfold" X-rays of these intricately-locked letters, to render the letter legible without having to actually open it! It's a pretty cool technique. The underlying paper is here: https://www.nature.com/articles/s41467-021-21326-w https://www.nature.com/articles/s41467-021-21326-w
- jedimastert 6y agoThat articles leads me to one of my kinds of YouTube channels, and my favor type of little corner of the internet: A vast array of oddly specific and niche knowledge I had no idea I wanted https://www.youtube.com/channel/UCNPZ-f_IWDLz2S1hO027hRQ https://www.youtube.com/channel/UCNPZ-f_IWDLz2S1hO027hRQ
- morsch 6y agoGreat style. Very old school. A candidate for (unintentional?) ASMR. It seems almost impossible to find these videos or channels intentionally, you can only stumble upon them.
- msp-m 6y agothis is one of those technologies - drop a letter from centuries ago onto an x-ray and let it get displayed on a computer screen - that will really make future tech look like "magic"
- hinkley 6y agoSome of the things we've done with old letters are fascinating. I remember when they figured out how to use spectral analysis to 'see' the solvents that soak into paper from the ink, allowing them to read words that had flaked off due to the ink or the paper delaminating, especially at the edges of paper.
- bb123 6y agoAh yes the original version of “warranty void if opened”.
- prionassembly 6y agoSomething like this is mentioned in the Hagakure, but I didn't understand what it was for until now.
- SamBam 6y agoIn the example image, it seems sealing wax is required to authenticate that the lock has not been opened. If sealing wax is going to be used anyway, why not just fold the letter and seal with wax like normal?
- function_seven 6y agoWith just a flat wax seal, is it possible to lift it off one surface, read the letter, then with a little extra wax, reseal the letter? If there are other pieces of paper held in the wax like a 3D matrix of sorts, it gets much more difficult to undo then redo the seal.
- hinkley 6y agoIf you can color match, probably. Rumor has it that Cardinal Richelieu's men had ways to read wax sealed documents. How many of these documents have multiple layers of meaning embedded in them? Steganography, euphemisms, inside jokes, shibboleths, what have you. I wonder how many things these letters say that we simply cannot read.
- signaturefish 6y agoIt's pretty easy to non-destructively lift a wax seal off of paper, with a sharp, hot knife and a bit of practice. You can then read the letter and reseal it with a touch more hot wax or the back of a heated spoon (to melt the back of the original seal). Not that I've ever done that, as a courier, in a live-roleplay game, ever. Repeatedly ;D Depending on the security level of the letter, of course, a non-letterlocked letter might be pretty readable even if sealed. A simple letter where the seal authenticates the sender but doesn't protect the contents might simply be folded in three and sealed closed - you can bend and flex such a letter without breaking the seal to read most of it. A more important letter being _protected_ by a seal might be folded into an ersatz envelope and then sealed on the join ... but that's most of the way to a basic letterlock. So, like all communications there's a tradeoff between complexity and security, and whether you're using the seal merely to authenticate the sender (which was pretty common) or also to protect the contents.
- akeck 6y agoThere's a sub-culture of origami related to this called "Envelope and Letter Folding".
- anorakoverflow 6y agoLooking at the links in the Wikipedia article I discovered this wonderfully “old web”-style page with various envelope folding guides[1]. I found it so endearing that I sat down and tried a few of them out, which was great fun. [1] http://www.orihouse.com/elfa.html http://www.orihouse.com/elfa.html
- Animats 6y agoThere was at one time a stapler-like device which did that automatically. It cut a slot and a tab, and pushed the tab through the slot.
- dhosek 6y agoThere still is. We have a couple of these in my house. It's not as effective as a metal stapler, but it works well enough for things that we don't need permanently connected (plus it's much safer for my 6-year-old kids to use).
- cbcrenshaw 6y agoI don't know much about the device you describe, but fastening papers with something like this is probably way better than staples if the goal is long-term storage. Staples and other metal fasteners are pretty destructive. The National Archives offers guidance for fastened document preservation, for example, here: https://www.archives.gov/preservation/holdings-maintenance/fastened-docs.html https://www.archives.gov/preservation/holdings-maintenance/f.... Staples can add a lot of unneeded bulk to records, too.
- codazoda 6y agoApparently these are called a "paper clinch".
- Animats 6y agoThere are crimp-type devices, and there are ones that cut a slot and tab. The slot and tab devices were patented in 1910. The main one was the "Bump Paper Fastener", which shows up on eBay now and then. So that's automatic letter-locking. [1] https://pdfpiw.uspto.gov/.piw?docid=01065904& https://pdfpiw.uspto.gov/.piw?docid=01065904&