The morning news. [volume] (Savannah, Ga.) 1887-1900, 1898-05-01
THE MORNING NEWS: SUNDAY, MAY ]. 1893

same conditions, it would go of AS far
as heat is concerned, If the dry gun cotton
Is exposed to a continued high tempera-
ture for a long time, il is likely to decom-
pose. undergoing chemical changes
which generate neat and may go far
enough to cause spontaneous combustion.
But no such condition is possible on
ship, because the gun cotton is always
carried in the torpedo heads and inspect
ed regularly TO see that IL remains wet
The heads are practically air tight. but If
any evaporation is noticed the cotton can
be dampened again by a regular means
arranged for that purpose"
The process by which so common and
harmless a substance as cotton is con-
verted into a high explosive is a compare
lively simple one. Pure raw cotton, or
ordinary cotton waste, is stepped in a So
luton of one part of nitric acid and three
parts of sulphurc acid. The nitric acid
is the one which renders the cotton ex-
plesive, the presence of the sulphuric be-
ing required only to absorb the water, thus
allowing the other acid to combine more
readily with the nearly pure cellulose of
which cotton consists. After the cotton
has soaked in the acids for several hours,
1t is taken from the pots and squeezed
through heavy rollers to extract all the
superfuous acid which it has not absorbed
Then ii is washed carefully and thorough
ly, still with the same object of removing
the free acid. If any of this remained, its
tendency would be to cause chemical
changes in the gun cotton and decompose
it. Formerly this washing was the last
| process resorted TO for the removal Of the
acid, but few years ago Sir Frederick
Abel found that the cells in the cotton fiber
so absorbed and retained the acid by capil-
larry attraction that the washing failed to
extract it entirely. To remedy this and
make gun cotton more pure Il Is now after
being washed passed through a machine
similar to that which grinds up the rags
in paper MILL Here it is crushed thor
oughly and afterwards washed again until
the last trace of free acid disappears, and
the cotton comes out in the form of a
SOFT white pulp, closely resembling the
| pulp OF which paper is made. This con-
| cludes the process Of actual manufacture
and IL now remains only to convert the
| gun cotton into the most convenient form
! for the use to which ii is to be put If it
| is to be employed in making powder it Is
drled and stored away in pulverized form,
! but II 1t is destined for filling torpedoes
1t must be compressed to a certain density
and moulded into the shape which will best
enable It to be packed into the torpedo
| heads. These shapes vary according to the
| design of the torpedoes and the method of
| packing. Sometimes they are disks and
sometimes cylinders, fiat squares or cubes
! II uneompressed and dry, the gun cotton
| would be extremely light, weighing no
more IMAM ordinary cotton batting but
| when made into the above forms IL is COM
| pressed to the density of about / or in
other words to a density of an equal
amount of water. The percentage of nois-
lure remaining in the gun cotton whom it
is packed into torpedoes varies between Is
ana 80. So safe from explosion. unless de-
tonated is brick of wet gun cotton that
II may be placed upon hot Goals. As the
| moisture dries off from the outside the
eotton makes off and burns up quietly Per-
| iectfy dfy gun cotton, when confined in q
strong case, will explode with great VIC.
renee IL exposed TO temperature of about
$50 degrees Fahrenheit.
defamation, or the firing of explosives bv
| intense shock, is a modern method for m.
I'll thirty years ago the application Of heat
was always used to bring about an ex-
plosion. 1t has now been discovered that
aetonation produces more powerful eff
1ect than explosion by means of heat. In
detonating the wet gun cotton in the tor
pedo heads, the primer of dry gun cotton
| which Is used weighs only a pound or
| thereabouty 1t is placed in contact with
the wet mass which in Whitehead tor
pedo consists usually of about $50 pounds.
Then, by means of fuse and illuminate
OF mercury cap fame is shot through
the disk of dry gun cotton. This explodes
instantly and with it the entire mass of
the wet cotton, producing tremendous re-
suits. The question of precisely how de-
donation takes place-that is, how so small
am initial explosion can suffice to decom-
pose an unlimited quantity of high ex-
plosive behind it-has caused much argu-
ment and many speeulations. BeFtelot
gives as an explanation that 'the shock
of the primary explosion communicates to
the layer of molecules in the immediate
proximity an enormously active force,
whereby the molecular edifice is shaken
10 pieces and the initial force is augmented
to a degree corresponding to the heat
evolved by decomposition. new shock
is thereby produced in the next layer, and
the action is repeated and so propagated
until the whole molecular system is COM
pletely destroyed"