Abstract: A compact and symmetrically arranged construction for electrical current indicating meters of small size. The meter construction comprises a concentrically pivoted coil which encircles a rounded magnetic fluxplate.

Abstract: A method of making a mixture of sensing material for a halogen vapor sensor characterized by providing granular activated Alumina (Al.sub.2 O.sub.3) and firing it in a sensitizing material, in the class of alkali metals including carbonates of sodium, lithium, potassium, cesium and rubidium, under controlled temperature conditions for a predetermined time to distribute the sensitizing metal throughout the interstices of the Alumina.

Abstract: A wet chlorine generator for providing precisely controlled rates of gas flow for instrumentation purposes, characterized by a safe and reliable gas source provided by precisely controllable electrolysis of a metal chloride electrolyte to form chlorine gas that is then passed through a flow regulating device into a gas conduit that guides the gas from the generator to associated instrumentation.

Abstract: A sensor assembly for a halogen gas leak detector characterized by including a tubular, porous, high purity Alumina (Al.sub.2 O.sub.3) element for supporting electrode and heater components in spaced-apart relationship relative to one another and a surrounding housing. The porous Alumina element is doped with an alkali metal by methods that cause the alkali metal to be distributed throughout the porous Alumina structure. The assembly is further characterized by incorporating a ribbon-like heater coil helically wound around the tubular Alumina element. In one embodiment of the invention the Alumina element is provided with a stepped end structure that effectively insulates the ends of an electrode mounted within the tubular element from the surrounding housing.