Three wicks arranged in a triangle in one reservoir give roughly three times the light of a single wick, but they also burn about three times the fuel and give off about three times the heat. The reservoir must be large enough to feed all of them, and the wicks should be spaced far enough apart that the flames stay separate.
Part of Oil Lamp Construction
Several wicks in one reservoir give more light than one, in step with the fuel and heat they add. They are the costliest way to brighten a lamp.
Several Small Flames Beat One Large One
The overview recommends multiple wicks for maximum brightness:
- 3 wicks in a triangle give roughly 3 times the light of a single wick.
- The reservoir must be large enough to fuel all wicks simultaneously.
- Multiple small flames produce less soot than one large flame.
The last point is a smoke-point effect. A single flame that is turned up past a certain height starts to smoke, whereas several smaller flames stay below that height. It holds only if each flame stays small and steady and the wicks are far enough apart that the flames do not merge into one tall sooty one.
Worked Example
Take tallow at about 25 ml/h per moderate wick (the overview’s figure) and the overview’s 240 ml cup.
- One wick: 240 ÷ 25 = 9.6 hours.
- Three wicks: 3 × 25 = 75 ml/h, so 240 ÷ 75 = 3.2 hours.
So three times the light costs a third of the burn time on the same fuel. With the energy arithmetic from the wick-sizing page, where 25 ml/h of tallow corresponds to roughly 236 W, three wicks would give 3 × 236 ≈ 708 W: as much as a small heater.
Method
Step 1: Choose a wide, stable reservoir. A closed-reservoir lamp or a large dish.
Step 2: Space the wicks. Make three holders in a triangle with gaps wider than a flame.
Step 3: Match the wicks. Use wicks of the same width so that all three burn evenly.
Step 4: Light and adjust. Light each, then lower any flame that rises above the others.
Common Mistakes
- Wicks too close. The flames merge into one large, sooty flame.
- Small reservoir. It empties in hours.
- Uneven wicks. The tallest flame smokes first.
Safety
The biggest heat and combustion-gas load of any lamp
Three flames consume three times the fuel and air. A multi-wick lamp in a small closed room is more likely to make carbon monoxide, especially if any flame smokes, and the early symptoms (headache, nausea, drowsiness) feel like ordinary tiredness. If anyone becomes sleepy, put the lamp out and get everyone into fresh air; ventilate with an inlet and an outlet. Never leave it unattended.
What’s Next
- Learn next: Soot & Ventilation — keeping a bright lamp from fouling the air
- Combine with: Glass Chimneys — a chimney helps burn each flame cleanly