Hydrometers; air analysis apparatus; batteries for lighting; thermionic valves; fire alarms; barometers; weighing machines; weighbridges; heat regulating apparatus, namely, thermostats; boiler control instruments; measuring devices for bathhouses and saunas, namely, water meters; electric installations for the remote control of industrial operations; Geiger counters; condensers; switchboards; electric regulating apparatus in the nature of voltage regulators for electric power; measures, namel...