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
Aqua-Lung Aqua-Lung Aqua-Lung was the first open-circuit, self-contained underwater breathing apparatus (or "SCUBA") to reach worldwide popularity and commercial success. This class of equipment is now commonly referred to as a diving regulator or demand valve. The Aqua-Lung was invented in Paris during the winter of 1942–1943 by two Frenchmen: the engineer Émile Gagnan and Naval Lieutenant ("lieutenant de vaisseau") Jacques Cousteau. It allowed Cousteau and Gagnan to film and explore more easily underwater. An earlier underwater breathing regulator, known as the "régulateur," was invented in France in 1860 by Benoît Rouquayrol. He first conceived it as a device to help