Editing Mona Lisa (section)

===Cleaning and touch-up===
The first and most extensive recorded cleaning, revarnishing, and touch-up of the ''Mona Lisa'' was an 1809 wash and revarnishing undertaken by Jean-Marie Hooghstoel, who was responsible for the restoration of paintings for the galleries of the [[Musée Napoléon]]. The work involved cleaning with spirits, touch-ups of colour, and revarnishing the painting. In 1906, Louvre restorer Eugène Denizard performed watercolour retouches on areas of the paint layer disturbed by the crack in the panel. Denizard also retouched the edges of the picture with varnish to mask areas that had been covered initially by an older frame. In 1913, when the painting was recovered after its theft, Denizard was again called upon to work on the ''Mona Lisa''. Denizard was directed to clean the picture without [[solvent]] and to lightly touch up several scratches on the painting with watercolour. In 1952, the varnish layer over the background in the painting was evened out. After the second 1956 attack, restorer Jean-Gabriel Goulinat was directed to touch up the damage to ''Mona Lisa''{{'}}s left elbow with watercolour.<ref name="mohen" /> In 1977, a new insect infestation was discovered in the back of the panel as a result of crosspieces installed to keep the painting from warping. This was treated on the spot with [[carbon tetrachloride]], and later with an [[ethylene oxide]] treatment. In 1985, the spot was again treated with carbon tetrachloride as a preventive measure.<ref name="mohen" />