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Argand

Argand Lamp, named after the inventor, a contrivance involving a special form of burner to render the incandescent surface a double one, and so increase the intensity of the emitted light. The arrangement was initially employed for oil-burning lamps, and consisted of a hollow cylindrical wick, a current of air required for the combustion of the inner surface passing up the middle. A glass cylinder was used as a chimney, to increase the draught and to steady the flame. In gas-burning lamps the burner itself is in the form of a hollow ring, the air coming up the central space as in the previous case.

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