Tom Welch, age 10, of College Station, Texas, for his question:

What keeps a candle flame burning?

The flame of a candle is a small fire and all fire must be fed with certain fuels. The candle uses oxygen from the air to consume gases in the waxy material from which it is made. Most modern candles are made from waxy paraffins and materials called stearins. These solid substances help to feed the flame when they melt and give off gases. The candle must have a wick down the center to make this happen.

When the wick is lighted, it warms a little of wax. Some of this melted wax gets warm enough to change into gases. These gases from the melting wax gather around the wick and supply the fuel that keeps the flame burning. The gentle little flame provides just enough warmth to melt the wax a little at a time. As the candle burns, it gradually uses up the wick and the warm wax. A candle sheds a gentle light, but its flickering flame is always ready to start a big fire. So let's make sure that a candle flame never gets a chance to touch a curtain or any other burnable object.