arry. "Well, uncle, the flame of
the candle is a little shining case, with gas in the inside of it, and
air on the outside, so that the case of flame is between the air and the
gas. The gas keeps going into the flame to burn, and when the candle
burns properly, none of it ever passes out through the flame; and none
of the air ever gets in through the flame to the gas. The greatest heat
of the candle is in this skin, or peel, or case of flame."

"Case of flame!" repeated Mr. Bagges. "Live and learn. I should have
thought a candle flame was as thick as my poor old noddle."

"I can show you the contrary," said Harry. "I take this piece of white
paper, look, and hold it a second or two down upon the candle flame,
keeping the flame very steady. Now I'll rub off the black of the smoke,
and--there--you find that the paper is scorched in the shape of a ring;
but inside the ring it is only dirtied, and not singed at all."

"Seeing is believing," remarked the uncle.

"But," proceeded Harry, "there is more in the candle flame than the gas
that comes out of the candle. You know a candle won't burn without air.
There must be always air around the gas, and touching it like to make it
burn. If a candle hasn't got enough air, it goes out, or burns badly, so
that some of the vapor inside of the flame comes out through it in the
form of smoke, and this is the reason of a candle smoking. So now you
know why a great clumsy dip smokes more than a neat wax candle; it is
because the thick wick of the dip makes too much fuel in proportion to
the air that can get to it."

"Dear me! Well, I suppose there is a reason for every thing," exclaimed
the young philosopher's mamma.

"What should you say, now," continued Harry, "if I told you that the
smoke that comes out of a candle is the very thing that makes a candle
light? Yes; a candle shines by consuming its own smoke. The smoke of a
candle is a cloud of small dust, and the little grains of the dust are
bits of charcoal, or carbon, as chemists call it. They are made in the
flame, and burned in the flame, and, while burning, make the flame
bright. They are burned the moment they are made; but the flame goes on
making more of them as fast as it burns them; and that is how it keeps
bright. The place they are made in, is in the case of flame itself,
where the strongest heat is. The great heat separates them from the gas
which comes from the melted wax, and, as soon as they touch the air on
the o