Senior conservator Tony Sigel takes us through the cleaning process for this bust of William Pitt, which Benjamin Franklin donated to Harvard in 1769. The sculpture was on view in our special exhibition “The Philosophy Chamber: Art and Science in Harvard’s Teaching Cabinet, 1766–1820” at the Harvard Art Museums from May 19 to December 31, 2017 and at The Hunterian at the University of Glasgow from March 23 to June 24, 2018. Learn more: http://bit.ly/2qnLpnU