Jacques Cousteau and Pierre-Antoine was released in 1954. During the 1940s, Cousteau is credited with improving the aqua-lung design which gave birth to the open-circuit scuba technology used today. According to his first book, "" (1953), Cousteau started diving with Fernez goggles in 1936, and in 1939 used the self-contained underwater breathing apparatus invented in 1926 by Commander Yves le Prieur. Cousteau was not satisfied with the length of time he could spend underwater with the Le Prieur apparatus so he improved it to extend underwater duration by adding a demand regulator, invented in 1942 by Émile Gagnan. In 1943 Cousteau tried
Jacques Cousteau with whom he had two sons, Jean-Michel (born 1938) and Philippe (1940–1979). His sons took part in the adventures of the "Calypso". In 1991, one year after his wife Simone's death from cancer, he married Francine Triplet. They already had a daughter Diane Cousteau (born 1980) and a son, Pierre-Yves Cousteau (born 1982), born during Cousteau's marriage to his first wife. The years of World War II were decisive for the history of diving. After the armistice of 1940, the family of Simone and Jacques-Yves Cousteau took refuge in Megève, where he became a friend of the Ichac family who