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From: "donald haarmann" <>
Newsgroups: rec.pyrotechnics
Subject: Re: Booby Trap Formula - Armstrong's Deadly Brew
Date: Fri, 10 Dec 1999 00:24:10 -0500

CD Ward <> wrote in message

> These things are generally loaded with Armstrong's Mix. The amount is
> quite small, but as noted, the stuff is very sensitive and potent. I met
> a fellow once who had a major horror story as a result of mixing an
> ounce of such material. He didn't know anything about its dangers, and
> as a result was maimed for life. One creepy part of the story is that he
> mixed it *dry* in a polyethylene tub with a stirring rod of some kind.
> The resulting explosion shattered the windows in the room where he was
> working and actually shattered the polyethylene into jagged, needle-like
> shards. The larger ones were extracted at the ER, while the smaller ones
> (undetectable by x-ray) worked their way out of his body for many, many
> months. Very ugly scene, indeed. I met him years afterward and the scars
> were still clearly visible, the hands, still, of course, damaged. This
> is not an experiment for the young amateur to emulate.

Donald J Haarmann aka The WiZ
American Fireworks News #51 December 1985

A letter of some months past detailing a reader's experiences with
nitrogen tri-iodide, has occasioned this missive on its potentially
lethal cousin, Armstrong's mixture.

Dear WiZ,

"Quite some years ago (30?) I happened upon the following in the Popular
Science Book of Formulas: Recipes, Methods & Secret Processes. (1932) 'A
sensitive detonating mixture is made of potassium chlorate 10 parts,
black antimony sulphide 5 parts and red phosphorus 1 part. Mix without
friction and at some distance from the operator's face. It is quite
sensitive to blows, very unlike [?] the potassium chlorate sulphur

"In those bygone days it was easy to obtain chemicals either from the
local druggist (who was probably amazed at the amount of potassium
nitrate my mother required for "preserving meat") or any chemical supply
house. One local chemical supply house would even give me a discount for
being a student. Therefore, obtaining the required reagents was not

"I started out by putting the mixture in 0000 gelatin capsules. Just
throwing them up into the air was sufficient to cause detonation upon
impact with the ground.

"One day a friend and I loaded quite a large amount into a cardboard tube
that BB's come in. We backed off quite a bit and fired upon it with a
Daisy pump action BB gun.  The second or third pellet found the mark,
resulting in a tremendous blast which rocked us back on our heels and
caused the propane gas tanks next to the house to ring as though they had
been struck by a hammer!

"This progressed to placing the material into a (you don't want to know).
Threw one off the roof of my friend's apartment house one night toward
the vacant lot directly behind.  However, its errant trajectory caused it
to land/detonate on the fire escape of an adjacent building! Scared the
S- out of someone who was peacefully watching TV with the window open.

"For the ultimate and final folly, had taken to adding magnesium to
increase sensitivity!  (Bet the second thing you did with your Chem Craft
chemistry set was to find all the fun things you could do with
Magnesium!) At that time our families both had country homes to which we
adjoined each summer. In the surrounding woods my friend and I had
constructed a small shack. On this fateful day while seated on the ground
at the back, my friend was seated on a stone wall directly in front
mixing, when KABOOM! WHAT A BLAST!!! The smoke blew away, and HE WAS
GONE!!!! GOOD GRIEF, what am I going to tell his mother???? He blew
himself up and I can't even find the pieces?!?!

 I am happy to report my grief was short lived, for these few seconds of
no little anguish were relieved by a plaintive cry of' Pssst -- Pssst I'm
over here, coming from some yards away. For as luck would have it, we
(he) were using a cardboard container, and "all" that happened was the
bottom blew out, resulting in numerous small holes in his blue jeans from
the unreacted phosphorus, and a not little-bit sore, blackened hand.
There is, in retrospect, no doubt in my mind that had mixing been
completed and the whole batch detonated, he would not have been able to
play the piano. Regards,"

Name withheld under pain of having flaming arrows being sent in the WiZ's
direction while he is making flash and report.

Yes, indeed. I would add the following quote from the American
Pyrotechnist for March 1978. "[a PGI member] dry mixed about a teaspoon
of potassium chlorate and [red] phosphorous, put it in a plastic 35mm
film container, and it ignited or exploded violently just from the slight
friction of snapping the cap on! He says that he has learned his lesson,
but the injuries to both hands were so disabling that he will not be able
to correspond with other members for about 2 months."

Some time ago an outfit called Howell Laboratories, Folly Beach, SC, sold
through an advertisement in the Shotgun News information on a "frictional
impact explosive"

The information turned out to be 5 small photo reproduced pages on the
compounding of Armstrong's mixture, for use in "Security Bombs" (booby
traps), "Smoke Screen" (combined with ammonium chloride), "Impact
Grenades" (gelatin capsules), "Explosive Rodent Traps" ("It let's you
know when a mouse or rat has been caught."), and "Impact Detonator', and
"Explosive Paint" ("This explosive paint lends itself well to practical
jokes.") [Sure!] One half pages were devoted to safety in compounding,
with the admonishment that "A pencil eraser sized piece will put the
loudest fire cracker to shame, while a thimble full will rival a stick of
dynamite." Perhaps somewhat over stated, but not by much.

An accident involving a substantial amount of Armstrong's mixture was
reported in Explosives and Their Power. Translated and Condensed from the
French of M. Berthelot. London 1892.

"The explosion which occurred in Paris, in the Rue Beranger, on May 14,
1878, may also be mentioned, in a store containing amorces [caps]
intended for children's toys.  These amorces were composed as follows:

 One kind, called single, of a mixture of potassium chlorate (12 parts),
amorphous [red] phosphorus (6 parts), lead oxide (12 parts), and resin (1
part); the others, called double, consisted of a mixture of potassium
chlorate (9 parts), amorphous phosphorus (1 part), antimony sulphide (1
part), flowers of sulphur (0.25 part), and nitre (0.25 part). The latter,
more sensitive to friction, averaged 0.01 grm. in weight. From six to
eight millions of these amorces pasted on paper slips, in lots of five
each, were piled up in the warehouse in boxes. A few of these having
become ignited by an accident, the origin of which was never clearly
ascertained, caused the whole to explode. One building suddenly gave way,
the facade being blown out, and the stonework hurled some distance. One
stone, measuring a cubic metre, was thrown to a distance of fifty two
meters. A great part of the adjoining building was also destroyed,
fourteen persons were killed on the spot, and sixteen received injuries.

"These terrible effects are explained when we consider that the weight of
the entire explosive matter contained in the amorces amounted to about 64
kgms., and that its force, owing to the composition of this matter, was
equal to a force of 226 kgms. of black powder. (These facts have been
taken from the report presented by the Committee of Inquiry.)

"It is essential that persons having explosive substances under their
charge should never lose sight of the conviction that, from the facts and
general truths which have just been stated, preventive measures should
always be prescribed on the hypothesis of an explosion." [Amen.]

I hope that these experiences point up the folly of working with
combinations such as Armstrong's mixture, its cousin the red explosive
mixture, and other less than safe and sane mixtures, i.e. potassium
chlorate and sulphur, or potassium chlorate and antimony sulphide, which,
by by, was used during the civil war in land mines! Further, although
Armstrong's mixture and the "red explosive" can be compounded "safely"
when wetted, what are you going to do with them when they have dried

Although the word "detonation" is commonly used in connection with
pyrotechnics, the only comp that has been tested and found to produce
true detonation is potassium chlorate and sulphur. However, it is my firm
belief that if Armstrong's mixture were to be tested, it too would be
found capable of detonating.

Other than toy caps and such, the only modern use for Armstrong's mixture
I have been able to locate are three US Patents (4,372,210, 4,191,947,
4,130,082) describing intrusion alarm systems using the radiant output
from MAGICUBE flash lamps to initiate a quantity of Armstrong's mixture
or SUPER BANG CAPS (potassium chlorate, red phosphorus, manganese
dioxide, sand and glue) to produce an audible alarm.

Finally, A Thought for Today: There are old pyro's and there are bold
pyro's, but there are no old unlucky pyro's!

 Even the WiZ does not know all (yet). Who, if any one, knows who
Armstrong was, and/or how his name came to be associated with the
combination of potassium chlorate and red phosphorous? WiZ


"Sir Williams Armstrong's explosive mixture for shells contains amorphous
phosphorus and chlorate of potash."

Rudolf Wagner  "A Handbook of Chemical Technology" D. Appleton and Company, New
York 1872.
Reprint by Lindsay Publications inc. pg. 546

Donald J Haarmann The WiZ

Published in -
The American Fireworks News #54 March 1986

Armstrong's mixture redux.

"Lasciate ogni speranza, voi chtentrate!"

Two letters have been received detailing their writers' experience with
this mixture. I have taken the liberty of editing them to protect the
identities of the authors.

"In the mid 1950's, the local 5&10 cent stores were selling for 10¢
each, cap guns of tin plated steel, somewhat thinner than the tinplate in
good cans, embossed to look somewhat like revolvers. All parts except the
hinge or pivot pins and two springs were of tin plate. No paint was

"Caps were 1¢ a roll and had 50 shots per roll. They were narrower
then common roll caps. The tissue cover readily pulled off, once
carefully started, revealing reddish lumps (Armstrong's mixture?) about
20% the mass of common roll caps of the day. These lumps could be scraped
off using a razor blade or an Xacto knife and were considerably more
friction sensitive than the American black cap mixture.

"While watching late nite TV movies one summer, I amassed enough of this
red mixture to fill a Jetex fuse tin (about 3/4 or possibly 1 tablespoon)
[of mixture]. It was then ignited inside the tin via Jetex fuse through a
hole in the lid. (Note minimal containment of charge.)

"As an adult pyro, now with some considerable experience... it [was]
absolutely THE MOST POTENT MIX I've ever played with."

The second letter reads as follows:

"I also have a copy of the Popular Science Book of Formulas. I leafed
thru it this morning; the pages describing "Fireworks" were blackened
with charcoal. - A' memories!

"When I was 14 I worked in the local drug store. The owner, a pharmacist,
would sell me anything and everything even acid and glycerin to make
Nitro, which I never did. I also bought gelatin capsules, and made
torpedoes. Some of the capsules were meant for animals, and were at least
an inch long and 1/2 inch wide. God, were they loud when made with
Armstrong's! I almost killed myself and gave it up."

Jack Stutting of Advanced Pyrotronics, Greenville, Michigan has provided
the following on the origins of this dreaded composition:

"Sir William Armstrong, an engineer from Newcastle, England. Originally
known for inventing types of hydraulic machinery and strengths of
materials and applied the results to making several types of modern
artillery. He was one of the first developers of rifled gun barrels and
also developed several successful breech loading guns, (artillery).  He
was appointed to the post of Superintendent of the Royal Gun Factory in
Woolwich.  This first production guns went into the field in 18606L To
work with this new designs in gunnery new propellants and primers for
these propellants had to be developed. Among many compounds developed and
tested the Armstrong's Mixture was one used quite often in priming the
propellant charges for large guns. Many of his designs still influence
the manufacture of modern artillery."

[The Ordnance Manual of 1862, provides instruction for producing
"friction primers for cannon" using "chlorate of potassa" and "sulphuret
of antimony," however, there is no mention of phosphorus in the book.

Dr. Ben Harriman of Florida, was kind enough to supply a copy of a letter
received from Herbert Ellern (March 1976) in which he states: "Nobody
seems to know who the 'Armstrong' was who first made the deadly mixture.
I have no doubt that soon after the discovery of red P in 1844, its
tremendous activity with oxidizing salts and some oxides such as PbO2 was
discovered. The Wm. G. Armstrong (1810 1900) mentioned in the Britannica,
an English engineer much engaged in ordnance, could have been it but he
surely was no chemist."

Ellern, Shimizu, and Tenney Davis have the following to say in their
respective books:

 "One combination of two solids exists in which a flaming or even
explosive reaction may take place on merely pushing the powders toward
each other or on exertion of very light pressure. This reaction occurs
when the powdered components are completely dry and the fuel is not
superficially oxidized. The two materials are red phosphorus and
potassium chlorate and a demonstration of their reactivity should be
performed only with a few milligrams of each component. When the
phosphorus has been kept for some time in an ordinary reagent bottle, the
spontaneity of the reaction may not be so obvious, but the final effect
may be just as disastrous, as has been shown many times when high school
students have appropriated and mixed together the two chemicals.

"This reaction is undoubtedly the most fascinating, and perhaps
theoretically the most interesting, solid reaction. It has been
ingeniously tamed in the modern safety match.

"Red phosphorus and chlorate can be mixed in comparative safety in the
presence of a liquid vehicle, provided both reactants are thoroughly
moistened by the vehicle before they come into contact. Using an aqueous
binder solution, small dabs of such a mixture form the explosive
ingredients of toy caps.

"[The] phosphorus/chlorate/binder combination are at the borderline
between spontaneous reaction and manageable, easily initiated, but stable
systems of reactive fuels and oxidizers."

 rates the sensitivity of "fundamental two component firework
compositions" on a scale from 1, to 5 the most sensitive. The combination
of potassium chlorate and red phosphorus rated 5; realgar and sulphur
were rated 4; milk sugar 3; while aluminium and charcoal were both rated

 "Toy caps are commonly made from red phosphorus and potassium chlorate, a
combination of the many with which the pyrotechnist has to deal. THEIR

"Mixtures of potassium chlorate and red phosphorus explode from shock and
from fire.  They do burn in an orderly fashion as do black powder and
most over pyrotechnic mixtures."

Here in basement D of the Schloss Zaubuer a quick check of the arcane
Bibliotheca WiZardae (perhaps the finest private collection of esoteric
pyro publications and nudist magazines in the western world) has turned
up seven US patents using either Armstrong's mixture or red phosphorus.
[Exclusive of those designed primarily to produce smoke.]

Charles Nelson's 1867 patent (65,764) for an "Improved toy torpedo and
explosive compound", provides the following: "The explosive material
which I prefer and have used successfully with my molded bodies is
compounded of as follows: One third amorphous phosphorus, one third
chlorate of posash, one sixth sulphur, one sixth pulverized chalk."
Compared to modern formulae this 33%/33/17/17 combination is long
phosphorus and short chlorate, perhaps to decrease sensitivity, or to in
crease the amount of smoke.

Issac Milband's patent number 157,856 of 1874, provides for a fulminate
compound composed of red phosphorus, potassium chlorate and charcoal, for
use in caps, primers and cartridges.

Patent 592,227 of 1897 for a "Match and composition for same," used red
phosphorus, potassium chlorate, antimony sulphide, charcoal, lead
chromate, gum benoin, dextrine and gum sandarac!

Charles Kalber's "Flashlight powder" patent number 2,098,341 makes
references to his British patent, 419,658 in which is provided a
detonation cap using a potassium chlorate, phosphorus mixture.

USP number 2,122,488 of 1938, describes a "Blow out imitator and the
method of packaging the same." Assigned to the Victory Fireworks and
Specialty Co., the patent describes a device used to imitate the
explosion of a tire blow out through the use of detonator in the form of
a fireworks torpedo.

"With this device one can safely plan an amusing trick by attaching the
device to a tire of a friend's car. When the car is moved and the
rotation of the wheel brings the detonator into engagement with the
pavement it explodes with a loud bang which is a perfect imitation of a
tire blow out.

"It has been found that the explosive will detonate without fail and
thereby create an amusing (?) situation and quite a joke upon the driver
of the car when he gets out and looks in vain for the blown tire.

"The explosive mixture is composed of red phosphorus and chlorate of
potash with gum arable as a binder and when first placed in its carrier
it is of liquid form and hardens into a cake or tablet. Continued setting
of the explosive mixture results in its binder drying out to such an
extent that handling the torpedo or any jar thereof will result in
breaking down the cake or tablet so that the explosive assumes a granular

"Ordinary toy torpedoes carry sand, pebbles, or some abrasive mixture in
conjunction with the explosive mixture to cause the same to explode when
struck. The present mixture however when it becomes of granular form,
will explode readily by even a slight blow without the use of sand,
pebbles or any abrasive mixture, with the result that the device is much
safer in use as it eliminates the flying particles of sand or the like,
which has always been incident upon the explosion of toy torpedoes as now
manufactured and sold."

A 1940 patent (2,194,480) for a "Noncorrosive priming composition,"
substitutes barium nitrate for potassium chlorate, in the red phosphorus
antimony sulphide mixture.

Fumio Hosoya's patent of 1966, (3,233,544) describes a "Signalling
Device" and more particularly an impact detonated, smoke or flame
emitting device, ie., a torpedo. The "detonating material includes
approximately 12 parts red lead, 1 part to which a bind ing agent is
added." Here the composition is intended not to produce noise but
sufficient heat to volatilize a smoke dye. The combination of red lead
and (ferro)silicon is of course a thermate (Goldsmith's) type comp,

donald j haarmann
An explosion may be defined as a loud noise
accompanied by the sudden going away of
things from the places where they were before.
                   Joseph Needham

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