Like what I make? Want fewer sponsorship ad reads? Consider contributing to my Patreon at https://patreon.com/OurOwnDevices The Tauchretter ('Dive Rescuer') was a German WWII escape set, used by submariners to bail out from a sinking submarine. Based on the rebreather principle, wherein exhaled air is scrubbed of carbon dioxide and recycled, the Tauchretter could provide its user with around 30 minutes of breathing gas. Rebreathers were widely used during the Second World War, not only as escape sets but also as diving equipment for combat frogmen - though their use of pure oxygen limited the depths to which they could be used. Today, rebreathers are extremely sophisticated, computerized devices used by cave divers, combat swimmers, and other specialists who require extended endurance and bottom time. SOURCES: https://joe-tauchretter.tripod.com/index.html https://www.warhistoryonline.com/instant-articles/swede-momsen-and-his-lung.html?Exc_D_LessThanPoint002_p1=1 https://www.history.navy.mil/content/history/museums/undersea/explore/exhibits/online/nedu/sub-rescue.html http://www.therebreathersite.nl/Zuurstofrebreathers/German/draeger_counterlung_to_swimmdive_device.htm https://www.usni.org/magazines/naval-history-magazine/2021/august/sinking-and-submerged http://www.therebreathersite.nl/Zuurstofrebreathers/English/photos_dsea.htm http://www.therebreathersite.nl/Zuurstofrebreathers/English/dsea.htm Video on the Sinking of HMS Thetis: https://www.youtube.com/watch?v=lFLf34hXmFM