In 1911 Enos B. Petrie patented a sort of umbilical, in fact the air hose with communication integrated.
After his inventions in 1902 – 1904 Petrie patented a US patent 984104 describing the following invention:
1. The combination with a diving suit, of a relatively large hose connected at its upper end with a pop valve, and a smaller air supply pipe extending through the hose and into the suit
2. The combination with a diving suit, of an air box having a pop valve, an exhaust pipe connecting to the diving suit and the box and connected to the diving suit and containing within the exhaust pipe, and wires for signalling and other purposes extending from the diving suit through the exhaust pipe to the air box.
3. The combination with a diving suit, of a hose connected with the suit, and wires for signalling or other purposes embedded in the hose
4. The combination with a diving suit of the air box having a controllable exhaust, an exhaust pipe connecting the diving suit and box, and an air supply pipe leading through the box and through the exhaust pipe to the diving suit.
Therebreathersite was founded by Jan Willem Bech in 1999. After a diving career of many years, he decided to start technical diving in 1999. He immediately noticed that at that time there was almost no website that contained the history of closed breathing systems. The start for the website led to a huge collection that offered about 1,300 pages of information until 2019. In 2019, a fresh start was made with the website now freely available online for everyone. Therebreathersite is a source of information for divers, researchers, technicians and students. I hope you enjoy browsing the content!