Q. Why does the flame of a candle point upwards?
A. The flame heats the surrounding air, which (being hot) rapidly ascends, and drives the flame upwards at the same time.
Q. Why is the flame of a candle pointed at the top, like a cone?
A. The upper part of a flame is more volatile than the lower parts; and as it affords less resistance to the air, is reduced to a mere point.
Q. Why is the upper part of a flame more volatile than the lower parts?
A. The lower parts of the flame are laden with unconsumed gas and watery vapour; which present considerable resistance to the air.
Q. Why is the flame of a candle blown out by a puff of breath?
A. As the flame of a candle is attached to a very small wick, a puff of breath severs the flame from the wick; and it goes out for want of support.
Q. Why does the flame of a candle make a glass damp, which is held over it?