Moberly and Jourdain's "Adventure"

The Petit Trianon is a Neoclassical château located on the grounds of the Palace of Versailles. Built between 1762 and 1768 during the reign of King Louis XV of France, the château was the location of the Moberly–Jourdain incident on August 10, 1901, in which two women allegedly experienced some form of time-slip or retrocognition.

Life partners Charlotte Anne Moberly (1846–1937) and Eleanor Jourdain (1863–1924) were wandering on the grounds nearby when they got lost and passed by a number of people in 18th-century clothing. One man was seated beside a garden kiosk, wearing a cloak and large shady hat; his face was "repulsive" and scarred by smallpox. Moberly said she noticed a lady in old-fashioned dress sketching on the grass who looked at them after they crossed a bridge; Moberly came to believe that the lady was Marie Antoinette. They began to think they might have seen events that took place on August 10, 1792, only six weeks before the abolition of the French monarchy.

Moberly and Jourdain published their story in a book titled An Adventure (1911), which was greeted mostly with skepticism. An explanation of the events was proposed by Philippe Jullian in his 1965 biography of the French poet Robert de Montesquiou, who at the time gave parties in the Versailles grounds where his friends dressed in period costume and performed tableaux vivants as part of the party entertainments. Psychologist Leonard Zusne suggested the incident was a "hallucinatory experience" that was elaborated upon over time. On the other hand, the incident was taken seriously by British philosopher J. W. Dunne (1875-1949) and English novelist and essayist J. B. Priestley (1894-1984).