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WOMEN IN A MUNITION PLANT ENGAGED IN THE MANUFACTURE OF
TRI-NITRO-TOLUOL, THE MOST IMPORTANT OF MODERN HIGH EXPLOSIVES]

The active agent in all these explosives is the nitrogen atom in
combination with two oxygen atoms, which the chemist calls the "nitro
group" and which he represents by NO_{2}. This group was, as I have
said, originally used in the form of saltpeter or potassium nitrate, but
since the chemist did not want the potassium part of it--for it fouled
his guns--he took the nitro group out of the nitrate by means of
sulfuric acid and by the same means hooked it on to some compound of
carbon and hydrogen that would burn without leaving any residue, and
give nothing but gases. One of the simplest of these hydrocarbon
derivatives is glycerin, the same as you use for sunburn. This mixed
with nitric and sulfuric acids gives nitroglycerin, an easy thing to
make, though I should not advise anybody to try making it unless he has
his life insured. But nitroglycerin is uncertain stuff to keep and being
a liquid is awkward to handle. So it was mixed with sawdust or porous
earth or something else that would soak it up. This molded into sticks
is our ordinary dynamite.

If instead of glycerin we take cellulose in the form of wood pulp or
cotton and treat this with nitric acid in the presence of sulfuric we
get nitrocellulose or guncotton, which is the chief ingredient of
smokeless powder.

Now guncotton looks like common cotton. It is too light and loose to
pack well into a gun. So it is dissolved with ether and alcohol or
acetone to make a plastic mass that can be molded into rods and cut into
grains of suitable shape and size to burn at the proper speed.

Here, then, we have a liquid explosive, nitroglycerin, that has to be
soaked up in some porous solid, and a porous solid, guncotton, that has
to soak up some liquid. Why not solve both difficulties together by
dissolving the guncotton in the nitroglycerin and so get a double
explosive? This is a simple idea. Any of us can see the sense of
it--once it is suggested to us. But Alfred Nobel, the Swedish chemist,
who thought it out first in 1878, made millions out of it. Then,
apparently alarmed at the possible consequences of his invention, he
bequeathed the fortune he had made by it to found international prizes
for medical, chemical and physical discoveries, idealistic literature
and the promotion of peace. But his posthumous efforts for the
a