The Argand lamp had a tubular wick mounted between a pair of concentric cylindrical metal tubes so that air is channeled through the center of the wick, as well as outside of it. A cylindrical chimney, in early models of ground glass and sometimes tinted, surrounded the wick, steadying the flame and improving the flow of air. It used a supply of good liquid oil, mostly colza or other vegetable oils as the fuel. This was supplied by gravity feed from a reservoir mounted above the burner. Aside from the improvement in brightness, the more complete combustion of the wick and oil required much less frequent snuffing (trimming) of the wick.
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