Since Vasari published his Lives of the Most Eminent Painters, Sculptors, and Architects in 1550, those in the art historical field have been rediscovering and dispersing facts and propositions about artists and artworks. Biographical gossip and process-oriented information often don't increase one's phenomenological understanding of art, but they do satiate the curiosity of an art enthusiast. Last night, Francis Bacon's Three Studies of Lucian Freud became the most expensive piece of art ever sold at $142,405,000 at Christie's Post-War & Contemporary Art Evening. As prices for art continue to rise, expensive works gain an almost mythic reputation, increasing curiosity about the true history behind famous pieces. The following 25 tidbits include facts about how artworks like Anish Kapoor's Cloud Gate are kept clean, how artworks are made—like Géricault's research with cadavers, and how artworks like Rembrandt van Rijn's dimming Night Watch have changed since their inception. Go beyond the surface of your favorite pieces with 25 Things You Didn't Know About Famous Works of Art.