The engraving in the Panthéon commemorates the death of Jean Sylvain Bailly, who was the first mayor of Paris and a prominent figure in the French Revolution. The engraving reads as follows:
Ici repose un Français, nommé Jean Sylvain Bailly, ancien président de l'Assemblée nationale, maire de Paris, et premier président de l'Assemblée constituante, tué d'un coup de canon le 12 novembre 1793, âgé de 54 ans, au même endroit.
Translated, this reads:
Here lies a Frenchman, named Jean Sylvain Bailly, former president of the National Assembly, mayor of Paris, and first president of the Constituent Assembly, killed by a shot from a cannon on the 12th of November 1793, at the age of 54, in the same place.
The engraving serves as a reminder of Bailly's contributions to the French Revolution and his tragic death.