Melchisédech or Melchisédec Thévenot (c. 1620 – 29 October 1692) was a French author, scientist, traveler, cartographer, orientalist, inventor, and diplomat. He was the inventor of the spirit level and is also famous for his popular posthumously published 1696 book The Art of Swimming, one of the first books on the subject and widely read during the 18th century (Benjamin Franklin, an avid swimmer in his youth, is known to have read it). The book popularized the breaststroke (see History of swimming) ; he was inducted into the International Swimming Hall of Fame in 1990. He also influenced the founding of the Académie Royale des Sciences (the French Academy of Sciences). Life Thévenot came from a family of royal office holders (nobles of the robe), which partly explains his wealth. He was reputed to speak English, Greek, Latin, Hebrew, and several oriental languages, including Arabic and Turkish. Thévenot's baptismal name was Nicolas, Melchisédech being added as the second (confirmation) name, almost certainly in honour of his maternal grandfather, Melchisédech Garnier (d. 1637), an avocat at the Parlement of Paris, and probably a Huguenot (given the Old Testament name). Thévenot was an amateur scientist and a patron of many scientists and mathematicians, maintaining correspondence with figures like Jan Swammerdam, whom he encouraged to tackle the origin of organisms. He was wealthy and well-connected, in 1684 becoming the Royal Librarian to King Louis XIV of France. He also served as ambassador to Genoa in 1647 and then to Rome in the 1650s. After the death of Pope Innocent X, he participated in the subsequent conclave. He died at Issy. Scientific studies Thévenot studied astronomy, physics, medicine, and magnetism, and demonstrated in the 1660s the possibility that atmospheric pulsations had something to do with human and animal respiration. Between 1658 and 1661 Thévenot conducted experiments on capillarity and the siphon. He proposed the use of lemon juice as a cure for various maladies, as well as ipecac as a remedy for dysentery. Thévenot can be credited in sponsoring a scientific study that contributed to the discovery of the nature and mechanism of fertilization both in humans and in animals in general. In April 1665, he wrote to his friend Christiaan Huygens (1629–95), a Dutch mathematician and astronomer: "We took the opportunity provided by the cold of recent months and applied ourselves to dissections and to investigating the Generation of animals" (Thévenot 1665). The