The Princeton union. [volume] (Princeton, Minn.) 1876-1976, 1915-04-01
POWDER and BALL
The Deadly Successors to Mans
First Crude Weapons.
FROM JAVELIN TO CORDITE.

Cannon and Guns Are Merely In the
Mature of Chemical catapults-The
introduction of Explosives and the
Princi pies Governing Them.
When the first man in the old stone
age thousands Of years ago threw his
first javelin against hairy mammoth
he put his foot over the threshold of
the problem Of explosives. For it
seemed to him-and our feelings today
are with hm-that it would be more
pleasurable If one could hurt and kill
ones enemy without the gratuitous
thrill Of having to sit on the massive
tusk on the verge of a cavernous
mouth or Of having to approach with
in a few PAGES of the huge legs which
might the next moment descend upon
,him. It would be more convenient to
stand at the cave entrance on a dizzy
ledge Of rock and hurl weapon at the
distant enemy.
So man was driven to invent the
2catapult and a gun is merely a chemi-
cal catapult The trigger is pulled
back like the leather of the catapult,
and the sudden and extraordinary ex.
pansion Of the explosive corresponds
to the elasticity Of the rubber or
spring, the essential feature of both
instruments being the employment Of
some source Of more than human pow
.er which can be made to yield up its
energy at given moment in the re-
CURED way.
Explosives are, therefore, tabloid en-
ergy or power, and it is a just reminder
Of the fact that some substances are
explosive generally, whereas quite
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 is
changed into steam, but if the spout
were sealed and the whole Of the wa
ter could be changed into steam in a
second there would be an explosion.
And the instance is good because it is
really a kitchen model Of a volcano.
Moreover, steam guns were used in
America In the sixties.
The essential idea Of an explosive is
then the violent release of some pent-
up thing; just the opposite, from this
standpoint, of the catapult, which
works by allowing Il 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, is
experienced as q sound. It is the
sound which is popularity called an ex-
plosion.
Now, it has been said that an explo-
sive is tabloid force, power, energy.
How is it made available? 1t is easy
to follow the mechanism of an explo-
sive further. Explosives, as common
~ used, are solid substances which, by
burning, produced almost instantane-
ously an extraordinary large volume Of
gases. The heat and pressure of a
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 Il 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 Il noise like ''pouf" and burns
quickly. Guncotton may be burned on
the hand-it is not to be recommended
as q fashionable hobby-without any
serious inconvenience. Indeed, gun
powder was first used as an incendiary
composition. But a firework or gun
charged with gunpOWder will explode
with a loud report and may cause ia
tai wounds.
GunpoWder is the best known ex-
plosive mixture It is made from the
commonest ngredients-carbon, sui
phur and saltpeter. There are several
notifications Of gunpowder, other
nltrates being substituted for the salt
peter-potassium nitrates. The nitrates
give the oxygen to the mixture, with
out which it would not burn at all,
other explosive mixtures containing
chlOrates which have the same amount
or oxygen as saltpeter and the nitrates.
The different powders are used in diff
ferent circumstances where a more
violent or a slower or a safe explosive
is required, for it 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 Glow" explosive. It's explosion is
slow, and its effect is less violently
descriptive.
Dynamite is probably the best known
high explosive, and the name does
not stand for one particular substance,
but for large class, which are, in eff
feet, diluted nitroglycerin and which
are generally used for blasting.
Guncotton may be described as a
nitrate Of cotton wool (Which the
chemist would call cellulose). Both
nltroglycerin and guncotton are less