The Chemistry of Powder and Explosives - Sciencemadness Dot Org

76 PYROTECHNICS
Otherwise and very good. Of saltpeter ten ounces, of sulfur
one ounce, of powder three ounces and a half, of charcoal
three ounces and a half.
To make them go up more suddenly. Take of powder ten
ounces, of saltpeter three ounces and a half, of sulfur one
ounce, of charcoal three ounces and a half.
For rockets weighing one pound. Take of powder one
pound, of soft charcoal two ounces, and of sulfur one ounce.
Otherwise. Of saltpeter one pound four ounces, of sulfur
two ounces, of soft charcoal five ounces and a half.
For rockets weighing three pounds. Of saltpeter 30 ounces,
of charcoal 11 ounces, of sulfur 7 ounces and a half.
For rockets weighing four, five, six, and seven pounds. Of
soft charcoal ten pounds, of sulfur four pounds and a half,
of saltpeter thirty one pounds. 29
Present practice is illustrated by the specifications tabulated
below for 1-ounce, 3-ounce, and 6-pound rockets as now manufactured
by an American fireworks company. The diameter of
Size 1
Saltpeter 36
Sulfur 6
Composition of charge No. 3 charcoal
No. 5 charcoal 12
Charcoal dust 7
OUNCE OUNCE POUND
3
35
5
5
17
INCH
1/4
11/16
7/16
INCH
INCH
Length of case 3 4 13
Outside diameter / .. 1/2
2 3/8
Inside diameter ,... 5/16
1 1/2
Overall length of spindle 2 3/4 4 12 3/4
Length of taper 2 1/2. 3 23/32 12
Choke diameter 5/32 1/4 3/4
the base of the spindle is, of course, the same as the inside diameter
of the case. That of the hemispherical tip of the spindle is
half the diameter of the choke, that is, half the diameter of the
hole in the clay plug at the base of the rocket. The clay rings
and plugs, formed into position by high pressure, actually make
grooves in the inner walls of the cases, and these grooves hold
them in place against the pressures which arise when the rockets
are used. The propelling charge is loaded in several successive
small portions by successive pressings, with hydraulic presses
29 Lorrain, op. cit., pp. 236-237.
6
30
5
12
12