Solo diving II. In the late 1940s, after the invention of the Aqua-lung by Cousteau and Gagnan, the first retail underwater breathing apparatus for sport was commercially marketed. As the sport expanded through the 1950s, several sporting organisations – notably the Young Men's Christian Association (YMCA) – began scuba training programmes for swimming enthusiasts, thus began the codification of what was believed to be proper practices for the expanding amateur sport of scuba diving. The buddy system was thought to be a useful corollary to the "never swim alone" edicts of the YMCA swimming and lifesaving programmes. Cousteau independently implemented a buddy
Jacques Cousteau where a commemorative plaque was placed. During his lifetime, Jacques-Yves Cousteau received these distinctions: Cousteau's legacy includes more than 120 television documentaries, more than 50 books, and an environmental protection foundation with 300,000 members. Cousteau liked to call himself an "oceanographic technician." He was, in reality, a sophisticated showman, teacher, and lover of nature. His work permitted many people to explore the resources of the oceans. His work also created a new kind of scientific communication, criticized at the time by some academics. The so-called "divulgationism", a simple way of sharing scientific concepts, was soon employed in other disciplines and