Decoding Rome’s old master graffiti.

Most accounts of the history of graffiti have the art form really taking off in the 1970s, but art historian C. Guichard dates its emergence to slightly earlier ,the 16th century. She chronicles her findings during time spent deciphering and dating the innumerable tags left on masterpieces by Raphael, Michelangelo, and others in the academies and palaces of Rome.

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