Creative Chemistry | Page 9

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 advancement of
civilization and the abolition of war did not amount to much and his
high explosives were later employed to blow into pieces the doctors,
chemists, authors and pacifists he wished to reward.
Nobel's invention, "cordite," is composed of nitroglycerin and
nitrocellulose with a little mineral jelly or vaseline. Besides cordite and
similar mixtures of nitroglycerin and nitrocellulose there are two other
classes of high explosives in common use.
One is made from carbolic acid, which is familiar to us all by its use as
a disinfectant. If this is treated with nitric and sulfuric acids we get
from it picric acid, a yellow crystalline solid. Every government has its
own secret formula for this type of explosive. The British call theirs
"lyddite," the French "melinite" and the Japanese "shimose."
The third kind of high explosives uses as its base toluol. This is not so
familiar to us as glycerin, cotton or carbolic acid. It is one of the coal
tar products, an inflammable liquid, resembling benzene. When treated
with nitric acid in the usual way it takes up like the others three nitro
groups and so becomes tri-nitro-toluol. Realizing that people could not
be expected to use such a mouthful of a word, the chemists have
suggested various pretty nicknames, trotyl, tritol, trinol, tolite and trilit,
but the public, with the wilfulness it always shows in the matter of
names, persists in calling it TNT, as though it were an author like
G.B.S., or G.K.C, or F.P.A. TNT is the latest of these high explosives
and in some ways the best of them. Picric acid has the bad habit of
attacking the metals with which it rests in contact forming sensitive
picrates that are easily set off, but TNT is inert toward metals and keeps
well. TNT melts far below the boiling point of water so can be readily
liquefied and poured into shells. It is insensitive to ordinary shocks. A
rifle bullet can be fired through a case of it without setting it off, and if

lighted with a match it burns quietly. The amazing thing about these
modern explosives, the organic nitrates, is the way they will stand
banging about and burning, yet the terrific violence with which they
blow up when shaken by an explosive wave of a particular velocity like
that of a fulminating cap. Like picric acid, TNT stains the skin yellow
and causes soreness and sometimes serious cases of poisoning among
the employees, mostly girls, in the munition factories. On the other
hand, the girls working with cordite get to using it as chewing gum; a
harmful habit, not because of any danger of being blown up by it, but
because nitroglycerin is a heart stimulant and they do not need that.
[Illustration: The Genealogical Tree of Nitric Acid From W.Q.
Whitman's "The Story of