mercury arc

American  

noun

Electricity.

1. a bluish-green electric arc that has passed through a mercury-vapor cathode.

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mercury arc British  

noun

1. 1. an electric discharge through ionized mercury vapour, producing a brilliant bluish-green light containing ultraviolet radiation

   2. ( as modifier ) See also ignitron

      a mercury-arc rectifier

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Etymology

Origin of mercury arc

First recorded in 1915–20

Example Sentences

The New York City subway system also runs on DC, and was using mercury arc rectifiers into the 1990s.

From Seattle Times

When one eventually came, in the 1920s, in the form of the mercury arc valve, AC was entrenched.

From Economist

Doctors advised patients to sunbathe, and children living at higher latitudes spent three hours per week soaking up rays in carbon or mercury arc lamps.

From Slate

This effect is perhaps best witnessed on viewing a line spectrum such as that of the mercury arc, focused upon a ground glass.

From Project Gutenberg

Under Dr. Robinson's direction were brought out the oscillograph, the mercury arc rectifier, the photophone.

From Time Magazine Archive