Take an ordinary wine bottle and place it in front of and within a few
inches of a lighted candle. Blow against the bottle with your mouth at
about four or six inches distant from it and in a line with the flame.
Very curiously, notwithstanding the presence of the bottle and its
interception of the current of air, the candle will be immediately
extinguished as if there were no obstacle in the way. This phenomenon
is readily understood when we reflect that the bottle receives the
current of air on its polished surface and divides it into two, one of
which is guided to the right and the other to the left. These two
currents, after separating and driving back the surrounding air, meet
again at the very spot at which the flame is situated, and extinguish
the candle.
[Illustration: MODE OF EXTINGUISHING A CANDLE PLACED BEHIND A
BOTTLE.]
It is evident that the experiment can be reproduced by putting the
candle behind a stove pipe, a cylinder of glass or metal, a
cylindrical tin box, or any other object of the same form with a
diameter greater than that of a bottle, but not having a rough or
angular surface, since the latter would cause the current to be lost
in the surrounding air.
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