Submarine Escape
Early submarines had a tendency to sink, and a number of accidents before the First World War made the Admiralty look into the possibility of developing an escape apparatus for use by trapped crews. One of these, designed by Captain S.S. Hall and Fleet Surgeon O. Rees, and manufactured by Siebe Gorman, briefly went into production.
It incorporated a canister containing ‘Oxylithe’, a special chemical which when breathed upon gave off oxygen and absorbed carbon dioxide. In 1903 to 1907 the Swiss Professor Georges Jaubert, invented Oxylithe, which is a form of sodium peroxide (Na2O2) or sodium dioxide (NaO2). As it absorbs carbon dioxide, it emits oxygen. It consisted of a hard helmet and a belted, long-sleeved tunic. Inside the tunic was a canister of sodium peroxide which gave off oxygen while absorbing carbon dioxide. The use of sodium peroxide was an interesting choice as it had a tendency to ignite when wet. The equipment was very bulky and doubts existed about the wearer’s ability to exit through the upper hatch of a submarine when wearing it. Despite its workable design, the Hall-Rees apparatus was phased out - one for each crew member simply took up too much room in a cramped submarine.