Somebody sent me a link to an interview with art historian Charlotte Guichard who has discovered the signatures and tags of famous artists on walls and furnishings in the Vatican- the graffiti of art history in other words.
Guichard claims that she has discovered Poussin’s signature (dated 1627) scratched on a mantelpiece under Raphael’s famous Expulsion of Heliodors.
“Under Raphael’s “The Expulsion of Heliodorus from the Temple” fresco at the Vatican, there is a period fireplace made from a very hard type of marble. The entire mantlepiece is engraved with the names of artists from the 17th century to the 19th century. This mantlepiece has been transformed through the centuries into an incredible monument of signatures. It’s like a monument to classicism created by artists across centuries. The earliest signature is by the painter Nicholas Poussin, dated 1627. Pensioners at the French Academy in Rome (founded in 1666) rediscovered his signature about a century later, when they were sent by the king of France to trace Raphael’s fresco and send the copy back to Versailles for the royal collection. The tracing process implies a direct contact with the original work. During this process, the academicians discovered Poussin’s century-old signature. Louis Michel Van Loo, a member of an important dynasty of painters, leaves his name there in 1729, and other artists will follow suit throughout the 18th century.”