These mantel lamps stand at 19.5 inches in height with a double-armed lamp in the center and two single-armed to each side.

Catalog Number: 2017.29.1

The Argand lamp is a type of oil lamp invented in 1780 by Aimé Argand. Its output is 6 to 10 candelas, brighter than that of earlier lamps. Its more complete combustion of the candle wick and oil than in other lamps required much less frequent trimming of the wick.

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These new lamps, much more complex and costly than the previous primitive oil lamps, were first adopted by the well-to-do, but soon spread to the middle classes and eventually the less well-off as well. Argand lamps were manufactured in a great variety of decorative forms and quickly became popular in America.

From Wikipedia: https://en.wikipedia.org/wiki/Argand_lamp