Abstract: An improved optical device in combination with means for holding the device in position before the eye including an optical device formed of an opaque mask for mounting before the eye, a horizontal transparent area extending substantially across the mask centrally thereof, an array of discrete circular transparent areas on the mask, the array being disposed below the horizontal transparent area and each circular area having equal diameters of between 0.5 and 1.2 mm. is characterized by an increase in the total aperture of the transparent areas on those portions of the opaque mask where the eye-to-mask distance increases thereby permitting a greater field of vision while limiting the influx of light.

Abstract: A portable body warming device is disclosed having a housing which encloses separately a water compartment and a salt compartment. The salt compartment has segmented chambers, each of which contains salt which reacts exothermically with water supplied by means of interconnecting tubes. Addition of the water to the salt is controlled such that the exothermic reaction is effected over a period of time and usefully serves to warm the body of a user. For use in emergency water immersion situations, an automatic double starting valve is disclosed.