Five Mile Beach weekly journal., 1915-04-16
POWDER AND BALL
The Deadly Successors to Mans
First Crude Weapons.
FROM JAvELlN TO coRDITE

Principles Governing Them.
When the first man In the old stone
age thousands of years ago threw his
first ~jayelin against a hairy mammoth
he put his foot over the threshold OF
the problem of explosives. For II
seemed TO him-and our feelings today
+ with him-that 1t would be more
pleasurable If one could hurt and kill
ones enemy without the gratuitom
thrill of having to sit on the massive
tusk IN the verge of a cavernous
mouth or of having to approach with
in a few PAGES of the huge legs which
might the mex moment descend upon
him. 1t would be more convenient ia
stand at the cave entrance on a dizzy
ledge of rock and hurl a weapon at the
distant enemy.
So man was driven to invent tho
catapult. and a gun is merely a chemi
cal catapult, The trigger is pulled
back like the leather of the c%atapult
and the sudden and extraordinary ex
pansion Of the explosive corresponds
to the elasticity of the rubber OF
spring. the essential feature of botl
instruments being the employment OF
some source Of more than human pow
er which can be made to yield up it
energy at a given moment in the re
quired way.
Explosives are. therefore, tabloid N
ergy or power. and it is u just reminder
of the fact that some substances are
explosive generally. whereas quite q
number of common things may be
made explosive by some particular
kind of treatment. When water boils
on the fire there Is no explosion as it l.
changed into steam. but If the spout
were sealed and the whole of the wa
ter could lie changed into steam In O
second there would be nm explosion
And the instance is good because 1t il
really a kitchen model of asvolcano
Moreover. steam guns were used in
America In the sixties.
The essential idea of an explosive Ia
then the violent release of some pent
up thing; just the opposite, from this
standpoint, OF the catapult, which
works by allowing u distended thing
the elastic-to contract suddenly
whereas all explosives release a com
pressed thing. The release gives rise
to an air wave. and this, Of course, Ii
experienced as a sound. 1t Is the
sound which is popularity called an ex
plosion.
Now, 1t has been said that an explo
sive is tabloid force. power, energy
How is 1t made available? 1t is easy
to follow the mechanism of an explo
sive further. Explosives, as common
ly used, are solid substances which. by
burning. produced almost instantane
ously an extraordinary large volume OF
gases. The heat and pressure of &
blow cause the burning to start. and
the burning also produces heat which
acting upon the gases. increases the
volume still further. 1t may be sug
gested that there is no obvious reason
why even n sudden and enormous ex
pansion should cause the damage Of
an explosion. And the suggestion Is
quite just.
1t is only when they are confined
that explosives are really dangerous
Gunpowder burned In the open merely
causes d noise like ''pouf" and burns
quickly. ouncotton may be burned OF
the hand-~it is not to be recommended
az a fashionable hobby-without any
serious Inconvenience. Indeed. gun
MI ma A~.1e 90 &c -. 4,aa,,dtarn
composition. But a firework or a gun
charged with g%unpowder will explode
with q loud report and may cause ia,
tai wounds.
Gunpowder is the best known ex
plosiye mixture. 1t Is made from the
commonest Experimentation. sui.
phur and saltpeter. There are several
notifications of g~unpowder, other
nitrates being substituted for the salt.
peter-potassium nitrates. The nitratei
give the oxygen to the mixture, with.
out which it would not burn at all,
other explosive mixtures containing
CELEBRATES which have the same amount
of oxygen as saltpeter and the nitrates
The different powders are used in dit.
ferent circumstances where a more
violent or n slower or a safe explosive
Is required. for 1t Is not always the
same effect which one asks from an
explosive. Velocity may at times be
sacrificed, say. in favor of a higher
weight of common shell. Gunpowder
Is a low" explosive. Its explosion Il
slow. and its effect is less violently
disruptive.
Dynamite is probably the best known
'high" explosive. and the name does
not stand for one particular substance,
but for a large class, which are. in eff.
feet, diluted nitroglycerin and which
are generally used for blasting.
[ Guncotton may be described as q
nitrate of cotton wool (Which che
chemist would call cellulose). Both
n~itroglycerin and %guncotton are less
useful as explosives themselves than
their d~arfvaf.ves although Russia and