The Chemistry of Powder and Explosives - Sciencemadness Dot Org

TOY CAPS 105
"It is to be noted," he says, 49 "that, while the first formula
affords a composition of great strength, the second is still more
violent. It is alo of such susceptibility that extraordinary care
is required in the handling of it, or a premature explosion may
result."
Chlorate compositions arc not safe for use in maroons. Black
powder is not noisy enough. Allen F. Clark has communicated
the following pcrehloratc formulas for reports for maroons. For
Potasbium percklorate
Sulfur
Antimony s,ulfide
Sawdust
Rosin
Fine charcoal
12
. 8
a flash report he uses a mixture of 3 parts of potassium permanganate
and 2 of aluminum
Toy Caps
Toy caps are commonly made from red phosphorus and potassium
chlorate, a combination which is the most sensitive, dangerous,
and unpredictable of the many with which the pyrotechnist
has to deal. Their preparation ought under no conditions to
be attempted by an amateur. Powdered potassium chlorate 20
parts is made into a blurry with gum water. It is absolutely essential
that the chlorate should be wetted thoroughly before the
red phosphorus is mixed with it. Red phosphorus, 8 parts, is
mixed with powdered sulfur 1 part and precipitated calcium
carbonate 1 part, and the mixture is made into a slurry separately
with gum water, and this is stirred into the other until
thoroughly mixed. The porridgelike imss is then spotted on
paper, and a piece of pasted tissue paper is placed over the
spotted surface in a manner to avoid the enclosure of any air
bubbles between the two. This is important, for, unless the tissue
paper covers the spots snugly, the composition is likely to crumble,
to fall out, and to create new dangers. (A strip of caps, for
example, may explode between the fingers of a boy who is tearing
it.) The moist sheets of caps are piled up between moist blankets
in a press, or with a board and weights on top of the pile,
and are pressed for an hour or so. They arc then cut into strips
49 Op. tit., Vol. 1, p. 166.
1
6
2
3
32
3
3