6. Voynich manuscript [Wikipedia]
The Voynich Manuscript is a medieval document written in an unknown script and in an unknown language. For over one hundred years people have tried to break the code to not avail. The overall impression given by the surviving leaves of the manuscript suggests that it was meant to serve as a pharmacopoeia or to address topics in medieval or early modern medicine. However, the puzzling details of illustrations have fueled many theories about the book’s origins, the contents of its text, and the purpose for which it was intended.
The document contains illustrations that suggest the book is in six parts: Herbal, Astronomical, Biological, Cosmological, Pharmaceutical, and recipes.