A. Because the outer cone _prevents the oxygen of the air_ from getting freely to the _middle of the cone_; and without the free access of oxygen gas, there is no such thing as complete combustion. 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?_ A. The _hydrogen of the tallow_ combining with the _oxygen of the air_, produce a "watery vapour," which is condensed by the _cold glass_ held above the flame. Q. _Why does our hand, held ABOVE a candle, suffer from the heat of the flame so much more, than when it is placed BELOW the flame, or on ONE SIDE of it?_ A. Because the hot gases and air (in their ascent) _come in contact_ with the hand placed _above_ the flame: but when the hand is placed _below_ the flame, or on _one side_, it only feels heat from _radiation_. Q. _Why is a RUSH LIGHT extinguished so much more quickly than a cotton-wicked candle?_ A. As the _rush_ wick is _smooth_ and _hard_, the _mere motion of the air_ (produced by carrying the candle from one place to another,) is sufficient to sever the flame from the rush. Q. _Why is it more difficult to blow out a COTTON wick?_ A. The _cotton_ wick is _quite full of small threads_ or filaments, which help to _hold the flame on the wick_, like the roots of a tree. Q. _Why does an EXTINGUISHER put a candle out?_ A. Because the air in the extinguisher _is soon exhausted of its oxygen_ by the flame: and when there is no _oxygen to support it_, the flame goes out. Q. _Why does not a candle set fire to a PIECE OF PAPER twisted into an extinguisher, and used as such?_ A. 1st--Because the flame very soon _exhausts the little oxygen_ contained in the paper extinguisher: and 2ndly--The flame invests the _inside of the paper extinguisher_ with _carbonic acid gas_, which prevents it from blazing. Q. _Why is a LONG WICK never upright?_ A. Because it is bent by its own weight. Q. _Why is a LONG WICK covered with an EFFLORESCENCE at the top?_ A. The knotty or flowery appearance of the top of a wick arises _from an accumulation of particles partly separated_, but still loosely hanging to the wick.