591,704. Respiratory appliances. LONDON, R. C. May 7, 1945, No. 11601. [Class 81 (ii)] In emergency oxygen supply apparatus for respiratory purposes wherein a frangible nozzle, connected to the supply container and closed at one end, extends into a pliable supply pipe so that the nozzle may be broken to release the gas by deformation of the supply pipe, a comparatively unyielding flexible member extends through the pipe to prevent flattening thereof. In Fig. 2, the supply cylinder, which is housed in an airman's dinghy or parachute pack, has attached thereto by union 17' a member in which the nozzle 18 is secured by plug 19. Supply tube 14 is affixed to this plug, and is prevented from kinking where it emerges from housing 21 by a spring 22. The other end of the tube is provided with a bayonet union piece 17 for coupling to the normal oxygen supply tube to the mask. A lever' 24 pivoted at 25 in the housing 21 may be actuated by a bowden wire 27 and disengageable coupling 26 to deform tube 14 and thereby to fracture nozzle 18. The free end of the bowden wire is attached to a handle projecting from the parachute pack. Lever 24 is formed with a lug 30 extending through a slot in housing 21 and engaging a lock wire 32, severing or deformation of the wire indicating that the lever has been operated. A cord or polyvinyl thong 34 is inserted in tube 14, being secured at one end to a ferrule 35 and knotted at the other between the pin and body of the bayonet joint, and serving to allow the passage of oxygen if the tube becomes kinked. A union 17" containing a non- return valve enables the cylinder to be recharged.