Naturalist, chemist.

Franklin may have met him during his trip to Paris (1769), when he met his father, Michel-Ferdinand (1714-1769), inventor and member of the Academy of Sciences.

Lived in England for several years. Known as the duc de Picquigny until his father’s death.

Travelled to Egypt, where he discovered the entry to a monument situated at Sakkarah, near Cairo. Member of The Royal Society of London (1764). Worked on Egyptian antiquities (1770). Performed various chemical experiments (1773).

Notorious for his violent temper. His highly publicized feud with Beaumarchais briefly landed the two men in jail (1773).

Studied the nature of air and asphyxiation (1775). Experimented on himself and had himself revived by his butler. He and Franklin became close friends.

Married to Marie-Paule d’Albert, daughter of the duc de Chevreuse, governor of Paris.