Mercury (element) is used in thermometers, barometers, manometers, sphygmomanometers, float valves, mercury switches, mercury relays, fluorescent lamps and other devices, though concerns about the element's toxicity have led to mercury thermometers and sphygmomanometers being largely phased out in clinical environments in favor of alternatives such as alcohol- or galinstan-filled glass thermometers and thermistor- or infrared-based electronic instruments. Likewise, mechanical pressure gauges and electronic strain gauge sensors have replaced mercury sphygmomanometers. Mercury remains in use in scientific research applications and in amalgam for dental restoration in some locales. It is also used in fluorescent lighting. Electricity passed through mercury vapor in a fluorescent
Demon in a Bottle he carries in his briefcase, flies out of the plane, and guides it to a safe landing in the ocean. Navy ships approach and soldiers help the passengers to safety, and bring Iron Man to an island base. They tell him the tank was thrown by Namor, who was defending a resident of the island that the soldiers were trying to remove, because the island is used as a toxic waste disposal site. Iron Man confronts and fights Namor, before it's revealed that the soldiers actually belong to the Roxxon Oil Corporation, which is secretly occupying the island to mine