Vergil's Aenead
Here is a much more typical manuscript book, from around the time of Gutenberg's invention. It consists of plain lines of text in a hand which is of the type that served as model for the development of Roman letter forms.
Virgil's Aenead was one of the textbooks for centuries. Lehigh's copy was closely studied by a 15th century student.
A Secret Lover? Books with doodles tell a lot about their owners.