No writer is immune either to censorship or (to what is not always easily distinguishable) angry response from his readers. Petrarch was not the exception who proves the rule. The 1549 Sonnets seen below is a magnificently bound volume but the splendor of its dress has not preserved its contents from the destructiveness all too clearly wreaked upon it, the work of a person deeply serious about making the text unreadable.
Stefano Colonna’s 1552 edition also shows defacement. The cause for these acts of censorship—both the 1549 and 1552 volumes exhibit what is unambiguously that, not mere anger—is obvious. Indeed, the same poems in each edition are defaced. Three of them are easier to see in the 1552 edition than in 1549: they are numbers 136, "Fiamma dal Ciel" ("Flames from heaven"), 137, "L'avara Babilonia" ("Greedy Babylon"), and 138, "Fontane di dolore" ("Font of sorrow").
Each criticizes the decadence of the papal court at Avignon, which Petrarch even compares to the Whore of Babylon—a pejorative whose sixteenth-century adoption by Protestants he could not have foreseen in the fourteenth century, when no Protestants existed. But Counter-Reformation censors clearly thought contemporary reformers likely to read Petrarch's criticism as prefiguring their criticisms of the Roman papacy of their own era, and they sought to eliminate these poems from the printed record. The uncensored state of a second copy of the 1552 edition however, indicates why the censor's life was unlikely to be an entirely happy one: you could never be certain that you had caught them all.