Some of the most enduring mysteries of linguistics (and archaeology) are written languages for which we have no dictionary -- no knowledge of the symbol-to-phoneme (or symbol-to-syllable, or symbol-to-concept) correspondences.
One of the most famous cases where that seemingly intractable problem was solved was the near-miraculous decipherment of the Linear B script of Crete by Alice Kober and Michael Ventris, but it bears keeping in mind that this wasn't the first time this kind of thing was accomplished. In the early years of the nineteenth century, this was the situation with the Egyptian hieroglyphics -- until the code was cracked using the famous Rosetta Stone, by the dual efforts of Thomas Young of England and Jean-François Champollion of France.
This herculean, but ultimately successful, task is the subject of the fascinating book The Writing of the Gods: The Race to Decode the Rosetta Stone, by Edward Dolnick. Dolnick doesn't just focus on the linguistic details, but tells the engrossing story of the rivalry between Young and Champollion, ending with Champollion beating Young to the solution -- and then dying of a stroke at the age of 41. It's a story not only of a puzzle, but of two powerful and passionate personalities. If you're an aficionado of languages, history, or Egypt, you definitely need to put this one on your to-read list.
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