Cooling a Candle Flame
Take a long length of copper wire, the thicker the better, and wind it loosely around a round ruler. When you have made a spiral coil about an inch and a half long, slip it off the ruler and leave a length of the wire to serve as a handle.
Now, light a candle, and hold the spiral over the flame. If the copper wire is ordinarily cold, the candle will slowly go out. Light the candle again and put the copper spiral in a gas flame for a few moments. Then hold it over the candle flame. This time the candle does not go out. Why?
In the first case, the wire being cold, it conducted the heat away from the flame and reduced its temperature to so low a pitch that it could not remain alight. In the second case, the wire was hot and it did not rob the flame if the heat it required to keep alight. It therefore continued to burn. It was not a case of putting the candle out as a conical extinguisher does.