Manchester Democrat. [volume] (Manchester, Iowa) 1875-1930, 1904-05-11
WATER VS.. FIRE.
Few People Understand the Chemical
Action Of the Elements.

Few People Understand the Chemical
Action of the Elements.
Few people can explain how water
puts out fire. They know it does and
they are satisfied; they make no fur.
Their investigation. The problem seems
simple enough on the fact of it, but
there are many simple chemical prob
lens that go to make it anything but
easy to solve.
The problem has often been asked
school children, who have taken chem.
istry and sciences, to test their knowl-
edge of the subjects, but in nearly
every case the answers were anything
but correct. The usual answer is
that the water makes the wood or
other material wet. and as fire won't
burn wet things it necessarily must
extinguish the flames. Such deduc-
lions are far from correct.
In order to understand the action
of water on fire one must have some
intimate knowledge of the properties
of fire. Fire." says Prof. Garrett
P. Serviss. "is a form of chemical
combustion in which flames make
their appearance. There may be com.
bustion without flames, but not with.
out heat. Wood in burning always
gives of flames, as do some kinds Of
coal, but there are other kinds of
coal that do not.
I'm the process of combustion there
must be two things, at least, con.
cerned. In the first place there must
be the combustible, or thing that
burns. and in the next case, there
must be some supporter of combus-
ton. When wood burns in the open
air the wood is the combustible and
the air the supporter of the combus-
ton"
People who have seen big fires have
probably noticed that during the pro.
gress of the blaze there have been
times when the flames seemingly died
out, would blaze up again with re.
doubled fury. The reason for this is
that the water which has been pour.
ed on has supplied oxygen to the
flames. giving them renewed vigor.
This is the case in high wind, when
the fire becoming Strengthened by
the fresh oxygen, gets flercer and
fercer and is thus harder to put out.
In dead calm. fire is always easy
to cxtinguish, for the reason that all
the oxygen In the vicinity OF the
flames has been consumed.
A little water is of no use in ex-
tinguishing a fire, for the very reason
that 1t is not enough to Offset the heat
of the flames, but is set off into its
component parts and is burned up in
the flames-the oxygen only making
the flames fiercer.
The question now arises how n lot
of water. instead of supporting com.
bustion, does the opposite and extin-
guishes the flames. The reason is
that a huge volume of water falling
upon the flames is too great for the
heat of the flames to disassociate into
its parts. but instead sort of extin
guishes the flames. Water has re.
markable property, that of high spe.
cific heat. Many people in watching
FA-hSA4Hg 6dil{ding nave noticed the
firemen pouring streams of water on
the blaze and the accompanying hiss
ing noise and rising steam. The for
nation of the steam has suddenly
drawn an immense amount of heat
from the combustion going on in the
building and SO has tended to cool
off the building materials, and subdue
the fury of the flames.
Because OF this great specific heat
capacity Of water and the consequent
absorption of heat from the fire to
form the steam there is not enough
heat left to release the oxygen from
the hydrogen, or, in other words, to
set the two combined gases burning,
thus the constant streams of water
pouring in and on the fire and the
clouds Of steam rising serve as sort
of blanket, which shuts off the air
from the flames and prevents them
from obtaining more oxygen. This
constantly being repeated tends to
deaden the blaze more and more until
it finally dies out.-Chicago Chronicle.