The times., 1899-06-10
IMPERFEcTIONs OF POWDER.
The Ordnance Burcau Undertakes to
Solve n Mooted Problem

ihc orunnnce burcnu Undertakes to
Solve Mooted Problem.
Capt. o. B. Mitcham. of the Ordnance
Department, has been directed by Gen. A.
r. Burlington. Chief of the Bureau of
Ordnance. to conduct full investigation
into the recent explosion at Sandy Hook
during trial of the ten-ineh gun. Captain
Mitcham has been ordered not to confine
mis- investigation merely TO the explosion
OF this gun. but to include the whole sub
Ject OF smokeless powders and high ex-
piosives The Ordnance Department has
already received a report from Sandy Hook
on the explosion, but it does not state
any definite conclusions as to the cause
OF the accident. The report explains that
the gun had already been fired several
times with three-quarter charges, but upon
firing full charge. the gun, which was a
sound. strong. and heavy one, exploded.
and the breeeh block was driven backward
with such force as to pass completely
through the bomb proof and into the ma
chine shop. killing one officer and wound
ing two men
Information received by the War Depart
ment on the subject is that the pressure
gauge. which was recovered. showed that
the pressure had mounted to some un-
known point beyond the range OF the in
strument-possibly to as much as fifty
pioyed was not an excessive one. as the
gun was only being proved by firing four
service charges. The officials of the Ord
! nance Department are Inclined to at
tribute the explosions OF smokeless powder
to some erratic action OF the powder due
to the form and shape OF the grain rather
than 10 its chemical composition. The
powder OF the Army differs from the Navy
In that the former Is mixed with guam
tity OF nitro -glycerine while the latter
Is purely mechanical mixture Ordnance
officers of the Navy express the belief
however. that the mingling OF nitro-gly-
cerine with Army powder is to some ex-
tent responsible for its unreliability 1t Is
pointed out that nitro glycerine will not as
simulate with the mechanical powder
compound. and being in an oily state, will
leave its given position in the grain of
powder. and when the powder is ready for
use the nitro -glycerine will be found con-
| centrated at one place. thus rendering the
powder more unreliable and Inclined TO
explode prematurely. recent article in
Engineering." British publication.
speaking of the use of these explosives
in the United States. says:
Suppose that instead Of mechanical mixture
We nave a chemical one. in which each little atom
oil oxygen IS in actual touch with the combustible
material In such compound the elements Of
explosion are so intimately commingIed that the
factor OF time does not appear to be an element
III their explosion: that is. they combine instsn-
tsneousiy. and detonate like a Eliminating cap
ferhaps the best example of an explosion of thi,
KIND Is found in nitro-glyeerine. True g1n-cot-
ton, that iS tri-nitro-ceuose, is another violent
explosive.
Nobel sought to make smokeless noyvde- ant
OF nitro-gycerine. He believed that Il, violence
might be tanned by combining with it some IN
eTt or siuggishiy burning material like collodion
cotton. But collodion cotton does not posses,
good keeping qualities; it is very much affected
by heat Soon after this there was similar
smokeless powder made. but instead OF using
co..odion o.. :otton. the inventor used true gun
pio'ives to form siow-burning powder.
This publication says: There can be no
question but what oil or grease does have
a very great influence upon preventing de-
tonation in explosives
The Navy Department has received rs-
ports OF many cases of high pressares
violent explosions. and detonations in the
continental powders which contain nitro
gycerine and gun-cctton. but no yaseline
or oil. but have never heard of a case in
| which the Government powder containing
yaseline or the powder containing oil bas
detonated.
recent improvement in this kind of
explosives leaves out the vaseline or castor
oil and substitutes in its place a small
! quantity OF urea. In order to produce a
/ very hard substance a large percentage
Of collodion cotton is employed. This kind
| of preparation closely resembles that used
at Sandy Hook in the trial OF the ten-inch
gun that exploded. Another feature OF the
powder used in this gun is that it had fine
multiple perforations. 1t is to these per-
I fOrations that the Army Ordnance De
partment are inclined to attribute the
blame for the accident. Powder with
these perforations has been tried IN Eng
| land and found liable to lead to .erratic
| action, that is. very high pressures and
unsteadiness in burning. This is regarded
as particularly true when the powder has
| been affected by heat. The theory is that
/ the fire runs into the small holes. where
/ it burns with very great violence, pro-
ducing a pressure and heat much superior
to that in the gun chamber itself and that
! this blows the powder into fragments and
/ leads to very high pressure