The Providence news. (Providence [R.I.]) 1891-1906, 1898-04-27
HIGH EXPLOSIVES.
Guncotton Is BY Far the Safest Of
Any Of Them.
Reason why IL is Employed Instead
OF Nitro-G .ycerine.

asked by Z reporter OF the Springfield kepub-
lican about the qualities Of this substance
which is used in ths torpedoes carried by the
ships OF thenavy, is by far the ssfest Of any
OF the high explosives. That Is the reason 1t
IL chosen instead Of nitro-glycerine rrepars-
tions. which. although they will produce
more powerful effects, are very dangerous
things to have on shipboard. They can be
exploded too easily by the application OF
heat, by shock, and, under some conditions.
by spontaneous combustion. But the sun
cotton. as long rs ii is wet, Is absolutely safe
end there is no trouble about preserving the
necessary degree Of moisture.
Precisely the same opinion regarding gun
cotton as nn explosive for naval warfare was
expressed by the superintendent Of one of the
largest powder manufacturing firms, a man
who has, mad much experience in the making
of gunpowder and guncotton.
Not only Is guncotton absolutely inert and
harmless 10 long as it is wet. he said, but 1T
does not necessarily follow that 1t will ex.
plode even when dry. or course, il Ia then
much more liable to do SO. but'if IL is undis-
turbed in any way considerable quantity
OF it might remain dry without any accident.
In our works we are extremely careful
about the way in which we handle dry gun
tions when IL is wet. On shipboarL the disks
Of dry cotton which are used rs primers to
detonate the wet are always kept away from
the magazine, either ON deck or In one of the
cabins The only danger from them would
be in case they were dropped while being
handled. The result then would not always
perhaps not usually-be an explosion, but
you never can tell with certainty. One of the
sabo se1.& y.a "A xI
not exploce. and the next time, under APP
parently the same conditions. 10 would 60 on
As far as heat is concerned. il the dry gum
cotton Is exposed to a continued high temper
ature for long time, 1t is likely to decom-
pose. undergoing chemical changes which gem
crate heat and may 60 far enough TO cause
spontaneous combustion. But no such condi-
tion is possible on ship because the cuncot-
ton is always carried in the torpedo heads
and insr ecied regularly to see that IL remains
wet. The heads are practically alright, but
il any evaporation is noticed the cotton can
be damLened aenin by regular means ar
ranged for that purpose.
The process by which SO common and
harmless a substance as cotton is converted
into high explosive Is u comparatively sim
pie one. Pure raw cotton or ordinary cotton
OF nitric acid and three parts Of sulphuric acid.
The nitric mid Is the one which renders the
cotton explosive. the presence Of the sulphuric
being require only to absorb the water. thus
allowing the other acid to combine more read.
lily with the nearly pure cellulose OF which
cotton consists. After the cotton has soaked
In the acids for several hours, it IL taken
from the pots and squeezed through heavy
vnlI to- nwfV all a.
which IL has not absorbed. Then 1t is washed
carefully and thoroughly still with the same
object Of removing the free ac,d If any Of
this remained. Its tendency would bc TO cause
chemical changes in the guncotton and de-
compose it, Formerly this washing was the
last process resorted to for the removal of
he free acid. but u few years ago Sir Freder.
ick Abel found that the cells in tha--cotton
fibre 81 absorbed and retained the acid by
capillary attraction that the washing failed
to extract il entirely. To remedy this and
make the guncotton more pure il is now, af
ter being washsd, passed thorough machine
similar to that which Rrinds up the rags in
paper mill. Here it Is crushed thoroughly
and aftcrward washed again until the last
trace of free acid disappears, and the cotton
comes out in the fern OF a soft, white pulp,
n ad.. This concludes the process Of actual
manuncture, AID IL now rem aims only to con.
vert the guncotton into the most convenient
torn for the use to which IL is to be put Ii is
to be employed Ia making powder. 1t Is dried
and stored away in pulverized form, but IL it
is designed for filing torpedoes, it must be
compresse TO n certain density and moulded
into the shapes which will best enable il TO
a. a..
vary according 10 the design OF the torpedocs
and the method Of packing Sometimes thy
are disks and sometimes cylinders. fat
squares. or cubes. If rncomprcssed and dry.
the guncotton would be extrenely light,
weighing no more than ordinary cotton bat
ting, but when made into the above forms it
is compressed to the density Of an equal
am cunt Of water. The percentage of mois-
ture remaining in tho guncotton when IL is
packed into torpcioes varies between Is and
80. So safe from explosion. unless de;onated,
is brick OF wet cunco;ton that 1t may be
off from the outside the cotton fakes off and
burns up quietly. Perfectly dry guncotton.
when confined in strong case. will explode
with great violence If exposed to temper
sture of about 820 degrees Fahreohcit.
Detonation, or the firing Of explosives by
intense shock. is a model N method, for until
30 years ago, the application of heat was al
way used to bring about an explosion. 1t has
now been discovered that detonation pro-
duces moro powerful effect than explosion
by mee rs Of heat In detonating wet guncot
ton in The torpedo heads. the primer OF dry
guncotton which Is used weighs only pound
or thereabouts II ia placed in cntact with
the wet mass. which in a Whitehead torpedo
consists usually Of about ESQ pounds Then.
by means of fuse and illuminate Of mercury
cap, fame is shot through the disk of drv
guncotton. This explodes instantly and with
II the entire mass of III. wet cotton. produc-
ing tremendous results. The question OF pre-
cisely how dctonaiiun takes plocc-that Is
Row so So II an initial explosion can suffice 10
deco,upf g. an unlimited quantity of high ex.
Jlosives behind it-hss canseu ~ uch argument
and many speculations. Ber eliot gives "a an
explanation that the shcrk of tho primary
explosion communicates to the layer of mole
cules IN tho iinnedi ,te proximity an enor
inouslg rc i've force, whereby the mole ,ular
edihce Is shaken to pieces and the initial
force is augm,nic 20 a degree correspond
ing to the heat evolved by decomposilion. a
new shock IL thereby produced in tho rext