The candle is cylindrical in shape and has a diameter of 20 mm. The length of the candle
was initially about 18 cm and changed slowly during observation, decreasing about 4 mm in
The candle is made of a translucent, white solid which has a slight odor and no taste. It is soft enough to be scratched with the fingernail. There is a wick which extends from top to bottom of the candle along its central axis and protrudes about 10 mm above the top of the candle. The wick is made of three strands of string braided together.
The candle is lit by holding a source of flame close to the wick for a few seconds.
Thereafter, the source of flame can be re-moved and the flame sustains itself at the wick.
The burning candle makes no sound. While burning, the body of the candle remains cool to the touch except near the top. Within about 5 mm from the top of the candle it is warm, but not hot, and sufficiently soft to mold easily.
The flame flickers in response to air currents and tends to be-come quite smoky while flickering. In the absence of air currents, the flame is in the form shown in the drawing, although it retains some movement at all times.
The flame begins about 4 mm above the top of the candle, and at its base the flame has a blue tint. Immediately around the wick in a region about 5 mm wide and extending about 8 mm above the top of the wick the flame is dark. This dark region is roughly conical in shape.
Around this zone and extending about 5 mm above the dark zone is a region which emits yellow light, bright but not blinding. The flame has rather sharply defined sides, but a ragged top.
The wick is white where it emerges from the candle, but from the base of the flame to the end of the wick, it is black, appearing burnt except for the last 2 mm where it glows red. The wick curls over about 4 mm from its end. As the candle becomes shorter, the wick shortens too, so as to extend roughly a constant length above the top of the candle.
Heat is emitted by the flame, enough so that it becomes uncomfortable in a few seconds to hold ones finger a few millimeters to the side of the flame or a few centimeters above the flame.
The top of a quietly burning candle becomes wet with a color-less liquid and becomes bowl-shaped. If the flame is blown, one side of this bowl-shaped top may become liquid, and the liquid trapped in the bowl may drain down the candle's side. As it courses down, the colorless liquid cools, becomes translucent, and gradually solidifies from the outside, attaching itself to the candle.
In the absence of a draft, the candle may burn for hours with-out such dripping. Under these conditions, a stable pool of clear liquid remains in the bowl-shaped top of the candle. The liquid rises slightly around the wick, wetting the base of the wick as high as the base of the flame.