Porpoise (scuba gear) Porpoise (scuba gear) Porpoise is a tradename for scuba developed by Ted Eldred in Australia and made there from the late 1940s onwards. The first Porpoise was a closed circuit oxygen rebreather, and the following models were all single hose open circuit regulators. This rebreather was developed by Ted Eldred in the late 1940s and early 1950s. Some were made and used for sport diving, but they did not go into full production. It was worn on the back without a casing. The bag was between the canister and valve assembly and the diver's back. It had two wide breathing
The Silent World: A Story of Undersea Discovery and Adventure and 16 pages of color photos, made available by "National Geographic Magazine". The hand-held work in Ektachrome "is the first ever made in significant depths, using artificial light and scientific color correction." The Silent World: A Story of Undersea Discovery and Adventure The Silent World (subtitle: "A story of undersea discovery and adventure, by the first men to swim at record depths with the freedom of fish") is a 1953 book co-authored by Captain Jacques-Yves Cousteau and Frédéric Dumas, and edited by James Dugan. Although a French national, Cousteau wrote the book in English. Cousteau and Émile Gagnan designed, built,