Omaha daily bee., 1915-10-10
MANY USES OF EXPLOSIVES
Smithsonian Institute Issues Inter
esting Bulletin on Making
Of Munitions.
BIa FAcToR 1N var Avn PEACE


Europe. ana discussion Is rife on the
American manufacture OF the same, IN
articles on explosives recently issued by
The Smithsonian Institution gives much
timely information on the subject
The paper is written BY Major Edward
r. o'Hern OF the Ordnance department.
United States army. and deais with the
importance OF the bo-cailed explosives and
the increasing extent OF their use and
production. as well as their composition.
uses, method OF employment, and the re-
suits accomplished.
An explosive" says Major O'Hern. "is
q substance Of which the molecules are
made up Of a number Of atoms or units
rather loosely bound together In an un-
stable condition. ready to seek new aud
simpler combinations upon the furnishing
OF a sufficient motive force to start the
operation. This IL usually supplied
through a primer ignIted by a slow-burn-
ing fuse, or by a wire heated by an cleo
trio current when started. the heat and
shock developed will cause a continuation
Of the action throughout the mass OF the
explosive. The enormous power that can
thus Be developed from comparatively
small quantity OF material Ia indicated by
The thousands Of fragments into which
q twelve-ihch armor-piercing projectilc
was broken by the decoration Of a burst
ing charge about 5h per cent Of its
weight"
ahrer Glasses of Explosives.
The author divides explosives into three
classes. prupi e. sive or prob' Iiinr expio-
sives, known es low explosives; detonatng
explosives. or hisu explosives; and de-
tonafora OF Eliminates. For all classes
the effect Of the explosion II dependent
upon the quantity OF gas and heat de-
veloped per unit Of weight and volume Of
the explosive. the rapidity OF the reae-
tion, and the character Of the confine-
nent, n any. given the explosive charge,
The rapidlty OF reaction vnries greatly
with different explosive substances and
with the manner In which the explosion
ls started.
Black gunpowder. srnokeiess powder and
black bIastine powders are known as low
explosives. for certain OF which. such as
smokelesk powder. the explosion does not
differ In principle from the burning OF
piece OF wood or other coubustble. The
combustion is very rapid. but IL surface
seton proceeding from layer TO layer
until the grain is consumed. Such ma
terials are known as low OF progressive
explosives although the eptai power de-
yeloped through the combustion OF unt
weight may be very great and would be
destructive unless properly controlled
High Power Explosives.
Iu high explosives such a. dynamite.
nltroglycerin. euncotton. some blasting
pow6erp, ana most OF the 'permiss bic
explosives" approved by the United
states Bureau Of Mines for use in mines
whore gas explosions are liable 20 oo-
cur, the progress Of the explosive re-
action IL not by burning from layer TO
LAYER. but the breaking up Of the initial
molecules gives rise 70 An explosive wave
which is transmitted with great velocity
IN all directions throughout the nase and
causes ia. almost instantaneous ccnver-
sion into gas. The velocity Of propaBa-
tion OF the detonnting wave has been de-
sermined for some materials 10 be more
than D.ea feet per second. or npproxi-
inately four miles per second; this form
Of material is used IN shells and for
bursting purposes. The progressive ennis
sion Of gas from a low explosive such
ns burning gunpowder. produces push
ing effect upon a projcctiie, whereas tho
sudden conversion Of an equal weight
OF material into gas, as would happen
with a high explosive such aa dynamite
or nitrogiycerin. would develop such
high pressure and shatterlng effect a.
TO rupture the gun
The action OF Eliminates IL much n,ore
brusque and powerful than that OF the
high explosives Since they can be de-
tonated by shock or the application OF
heat, they are used In primers and fuses
10 start action In both low and high ex-
plosives. one OF the most important full
inmates is illuminate of mercury. which
produces a pressure OF about $500 at
mospheres,
Big Factor an History.
Al no time In she history Of the World
have explosives played such a mighty
part In deciding the destiny OF nations
AZ they are playing today IN the prose-
cution OF The general European war;
Their extensive use'in the mighty engines
or destruction such AS the submarine
mine. tho torpedo and IN projectiles
thrown from cannon 20 great distances
eish marvellous accuracy. Il resulting In
loss o. life and destruction OF property,
On an unprecedented scale.
Beginning with black powder, the earl
lest record Of which In actual war was
in the fourteenth century. the author
follows ths development Of powder
throagh TN early staxes of brown pow
der 60 the two principal forms Of smoke
loas peWecr for military purposes. nltro-
esllnloss and nitroslycerin. stating that
he use Is quite evenly divided; the
United states army and navy the French
army and navy. ana the German army
using the former. and the British army
and navy and tina German navy using
the latter. He then gives much detailed
information coneernlng the manufacture.
iils. source Of supply and tests Of smoke
ieas powder manufactured from nitro
ceIiulone or guncotton. FoilOwing which,
subjects relating 10 life Of guns. bursting
charges for projoctiies, arnor-plercing
projecfilts high explosive shells. shrap-
mel. fuses. aeropiane bombs. means OF
isnitins explosives. mines. torpedoes and