Porpoise (scuba gear) Porpoises still exist. Only a few of these early models are known today, the rarest being the CA-2, made for use with two tanks. 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
Scuba set of 1918), and Commandant le Prieur's hand-controlled regulator in France (as of 1926); see Timeline of diving technology. This system consists of one or more diving cylinders containing breathing gas at high pressure, typically , connected to a diving regulator. The demand regulator supplies the diver with as much gas as needed at the ambient pressure. This type of breathing set is sometimes called an "aqualung". The word "Aqua-Lung", which first appeared in the Cousteau-Gagnan patent, is a trademark, currently owned by Aqua Lung/La Spirotechnique. This is the first type of diving demand valve to come into general use, and