"The World's Most Mysterious Manuscript"

The Voynich manuscript, described as "the world's most mysterious manuscript", is a work which dates to the early 15th century (1404–1438), possibly from northern Italy. It is named after the book dealer Wilfrid Voynich, who purchased it in 1912. 

Some pages are missing, but the current version comprises about 240 vellum pages, most with illustrations. Much of the manuscript resembles herbal manuscripts of the 1500s, seeming to present illustrations and information about plants and their possible uses for medical purposes. However, most of the plants do not match known species, and the manuscript's script and language remain unknown. Possibly some form of encrypted ciphertext, the Voynich manuscript has been studied by many professional and amateur cryptographers, including American and British codebreakers from both World War I and World War II. It has defied all decipherment attempts, becoming a famous case of historical cryptology. The mystery surrounding it has excited the popular imagination, making the manuscript a subject of both fanciful theories and novels. None of the many speculative solutions proposed over the last hundred years has yet been independently verified.

The Voynich manuscript was donated to Yale University's Beinecke Rare Book and Manuscript Library in 1969, where it is catalogued under call number MS 408 and called a "Cipher Manuscript".