What is an Argand lamp and why is it important?

An Argand lamp employs 'a double current of air; which consists...of a wick, shaped like a hollow cylinder, enclosed in a glass tube'[70]. The heat from the oil's combustion produces a vigorous draught and abundant air circulation both internally and externally[70].

The Argand lamp is important because it was a pioneer in improving the lamps used in lighthouses[70]. It also stimulated further inquiry by others, such as Carcel and Rumford, to create newer and better lamps[70][80].