This is Pietra del paragone politico by Trajano Boccalini (1556-1613), an Italian political satirist whose writings were influential during the late Renaissance.  Boccalini died before the publication of this work, which is a scathing attach on the Spanish for the treatment of their subjects during their occupation of the Kingdom of Naples.

Like many works that challenged authority, this one was issued with a false imprint for the protection of its printer.  It has a beautiful engraved title page featuring a king talking with a courtier.  It's small – just the right size to be concealed in a pocket.  And, interesting for us (or for this librarian, at least), the endleaves are covered with pen trials.  Find it in the MERLIN catalog, and come by to see it in person.