Belding banner. (Belding, Mich.) 1889-1918, 1897-10-21

EXPERIMENTAL DUST EXPLOSION.
til at length the constituents of the
wood have united with the oxygen of
the air.
"If the log had been split into cord
wood, the burning would have taken
place in much shorter time. If the
cord wood were split into kindling wood
and piled so that the air had free ac-
CESS, the burning would take place still
more rapidly If the wood were ground
into powder-powder so fine that it
would float in the air-combustion
would take place so rapidly as to result
in an explosion. So powerful is the in
fluence of the division that many sub
stances which in bulk are either rela-
lively noncombustible or to be ignited
only with considerable difficulty are,
when in a fine state of division, readily
ignitible. As an example of a substance
not combustible in the ordinary sense
Of the term iron may be taken. When
finely divided, either into filings or by
the process of rusting it burns readily.
Simple as the above explanation is,
the dust explosion phenomenon has been
explained by number of theories
whose falsity was equaled by their in
genuity Argument once was advanced
that the explosion is due to some form
of spontaneous combustion. Others have
endeavored to show that it resulted
from certain vibration of the dust
PARTICLES afoat in the air. The fact is
that the ignition must come from actu-
al light or high degree of heat in
some other form. Experiment has shown
that other possible origins for the explo-
sion are out of the question.
A delightfully."- interesting experiment
with dust explosion is performed with
set of apparatus so simple as to hard
ly deserve the name, comprising, as
it does, only pair of bellows, an alco-
hol lamp or piece of candle and a cou-
pie of sticks fastened on edge in the
form of " For material fine flour
will do. Put couple Of tablespoonfuls
or so of -four in the point of the V,
where the two side pieces should be
joined snugly BY this arrangement a
puff with the bellows, held at the open
end of the V. will cause the flour to fly
up in little cloud.
Before making this puff however,
light the candle or lamp Then push the
bellows sharply, and woof the cloud
of flour instantly bursts into a sheet of
flame The flame goes out almost inn
mediately.
Essentially the same apparatus can
be applied in the construction of box
made purposely for these experiments
The V of sticks is placed at the bottom
of the box, as is the light The box is
fitted with lid pushing tightly down
over an upward extension which might
be termed a chimney The lid, being
free to move under pressure, is the part
Of the apparatus which is to show the
force of the explosion The chimney, i'm
concentrating the area of the explosion,
also concentrates its force on the lid
Light the lamp, as before, and dis
pose the flour. Put on the upper side of
the box. hook it down and jam the lid
down on to the chimney A puff with
the bellows. inserted at small hole
suitably situated near the bottom of the
box, blows up the flour inside The ex-
plosion Immediately following blows
the chimney lid several feet mp in the
air.
Using small quantity of lycopodium
powder in place of -four, Mr.. Kennicott
shot the lid, weighing no less than