Support WBURWith Chemistry And Care, Conservators Keep Masterpieces Looking Their BestPlay07:09Download AudioSusan StambergJune 27, 2017 ShareSenior conservator of paintings Ann Hoenigswald works to fill in elements of Paul Cézanne's Riverbank c. 1895 in the National Gallery of Art's Paintings Conservation Lab in Washington, D.C. (NPR)