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2021-03-10, 12:35
Sleuths Read Old Booby-Trapped Letters Without Opening Them
People once folded their correspondence in intricate ways, known as “letterlocking,” to keep out snoops. A fancy new imaging technique sees right through it.
https://www.wired.com/story/sleuths-read...ening-them
People once folded their correspondence in intricate ways, known as “letterlocking,” to keep out snoops. A fancy new imaging technique sees right through it.
https://www.wired.com/story/sleuths-read...ening-them