A Classic Example,

of never judge a book by it's cover,

 on the outside, almost any old book,

 but what treasures it contains! 

the book is called Mira calligraphiae monumenta (The Model Book of Calligraphy), 

and is the result of a collaboration across many decades between a master scribe, the Croatian-born Georg Bocskay, and Flemish artist Joris Hoefnagel,

 In the early 1560s, while secretary to the Holy Roman Emperor Ferdinand I, Bocksay produced his Model Book of Calligraphy, showing off the wonderful range of writing style in his repertoire, 

 some 30 years later (and 15 years after the death of Bocskay), Ferdinand’s grandson, who had inherited the book, commissioned Hoefnagel to add his illustrations of flowers, fruits, and insects, it would prove to be, as The Getty, who now own the manuscript, to comment, “one of the most unusual collaborations between scribe and painter in the history of manuscript illumination”

 the book not only contains passages, but also details the way that letters are formed both in upper,

 and lower case, a real example of not to judge a book by it's cover.