It is a small book that has been included in the Machiavelli box by the Dal Nero editions, together with two playing card sets.

The cards on the table belong to everybody and during each turn they may be rearranged in order to form better combinations.
Machiavelli is one of the most dynamic card games and the book explains its history, rules, variations and shows some examples. Today this game is known all over the world with the name Rummikub, and it is common to see versions of it in which, instead of cards, there are small  "domino-like" tiles, much easyer to move around on a table than cards.