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
Porpoise (scuba gear) single-hose open-circuit scuba made in the world. Ted Eldred in Melbourne in Australia started designing it in 1948 to "design around" the Cousteau-Gagnan aqua-lung patent, and to get rid of air supply restrictions that affected early Cousteau-Gagnan-type aqua-lungs. He started making it commercially in 1952. The Royal Australian Navy adopted it. It was the origin of single-hose scuba regulators. It was much used by Australian scuba divers. The picture shows the CA-1, a set with one cylinder with its valve at the bottom, strapped directly to the back with rucksack-type straps without backpack plate or buoyancy aid, with a single-hose