One painting tried to save the scientist Lavoisier from the guillotine. The Met discovered it after more than 230 years

Federico Carò, scientific researcher at the Metropolitan Museum of Art in New York, tells how the team he is part of discovered – through technologies such as X-ray fluorescence spectroscopy and Raman spectroscopy – what the portrait of the spouses (and scientists) was hiding Lavoisier made by Jacques Louis David in 1788, one year before the start of the French Revolution.