The Chemistry of Powder and Explosives - Sciencemadness Dot Org

74 PYROTECHNICS
John Bate and Hanzelet Lorrain understood that the heavier
rockets require compositions which burn more slowly.
It is necessary to have compositions according to the
greatness or the littleness of the rockets, for that which is
proper for the little ones is too violent for the large—because
the fire, being lighted in a large tube, lights a composition of
great amplitude, and burns a great quantity of material,
FIGURE 23. Rocket, Lorrain, 1630. Substantially as rockets are made today.
After the propelling charge has burned contpletely and the rocket has
reached the height of its flight, the fire reaches the charge in the head
which bursts and throws out large and small stars, serpents and grasshoppers,
or English firecrackers. The container, which is loaded into the
head of the rocket, is shown separately with several grasshoppers in the
lower right-hand corner of the picture.
and no geometric proportionality applies. Rockets intended
to contain an ounce or an ounce and a half should have the
following for their compositions.
Take of fine powder (gunpowder) passed through a screen
or very fine sieve four ounces, of soft charcoal one ounce,
and mix them well together. 28
Otherwise. Of powder sieved and screened as above one
pound, of saltpeter one ounce and a half, of soft charcoal
28 The charcoal makes the powder burn more slowly, and produces a trail
of sparks when the rocket is fired.