What device, invented by Peter Cooper Hewitt in 1902 and obsolete by 1975 with the introduction of devices such as the silicon diode and thyristor, converts alternating current to direct current by means of putting electricity through vapor?
Mercury vapor rectifier Mercury-arc valve Mercury arc rectifier Mercury-arc rectifier Mercury-vapor rectifier Mercury arc valve
mercury arc rectifier mercury arc valve mercury vapor rectifier
mercury arc rectifier
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Mercury arc rectifier