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Today's
rockets are remarkable collections of human ingenuity that have their roots
in the science and technology of the past. They are natural outgrowths
of literally thousands of years of experimentation and research on rockets
and rocket propulsion.
One of the first devices to successfully
employ the principles essential to rocket flight was a wooden bird. The
writings of Aulus Gellius, a Roman, tell a story of a Greek named Archytas
who lived in the city of Tarentum, now a part of southern Italy. Somewhere
around the year 400 B.C., Archytas mystified and amused the citizens of
Tarentum by flying a pigeon made of wood. Escaping steam propelled the
bird suspended on wires. The pigeon used the action-reaction principle,
which was not stated as a scientific law until the 17th century.
About three
hundred years after the pigeon, another Greek, Hero of Alexandria, invented
a similar rocket-like device called an aeolipile. It, too, used steam as
a propulsive gas.
Hero mounted a sphere on top of a
water kettle. A fire below the kettle turned the water into steam, and
the gas traveled through pipes to the sphere. Two L-shaped tubes on opposite
sides of the sphere allowed the gas to escape, and in doing so gave a thrust
to the sphere that caused it to rotate.
Just when the
first true rockets appeared is unclear. Stories of early rocket-like devices
appear sporadically through the historical records of various cultures.
Perhaps the first true rockets were accidents. In the first century A.D.,
the Chinese reportedly had a simple form of gunpowder made from saltpeter,
sulfur, and charcoal dust. To create explosions during religious festivals,
they filled bamboo tubes with a mixture and tossed them into fires. Perhaps
some of those tubes failed to explode and instead skittered out of the
fires, propelled by the gases and sparks produced by the burning gunpowder.
 The
Chinese began experimenting with the gunpowder filled tubes. At some point,
they attached bamboo tubes to arrows and launched them with bows. Soon
they discovered that these gunpowder tubes could launch themselves just
by the power produced from the escaping gas. The true rocket was born.
The date reporting the first use
of true rockets was in 1232. At this time, the Chinese and the Mongols
were at war with each other. During the battle of Kai-Keng, the Chinese
repelled the Mongol invaders by a barrage of "arrows of flying fire." These
fire-arrows were a simple form of a solid-propellant rocket. A tube, capped
at one end, contained gunpowder. The other end was left open and the tube
was attached to a long stick. When the powder was ignited, the rapid burning
of the powder produced fire, smoke, and gas that escaped out the open end
and produced a thrust. The stick acted as a simple guidance system that
kept the rocket headed in one general direction as it flew through the
air. It is not clear how effective these arrows of flying fire were as
weapons of destruction, but their psychological effects on the Mongols
must have been formidable.
 Following
the battle of Kai-Keng, the Mongols produced rockets of their own and may
have been responsible for the spread of rockets to Europe. All through
the 13th to the 15th centuries there were reports of many rocket experiments.
In England, a monk named Roger Bacon worked on improved forms of gunpowder
that greatly increased the range of rockets. In France, Jean Froissart
found that more accurate flights could be achieved by launching rockets
through tubes. Froissart's idea was the forerunner of the modern bazooka.
Joanes de Fontana of Italy designed a surface-running rocket-powered torpedo
for setting enemy ships on fire.
 By
the 16th century rockets fell into a time of disuse as weapons of war,
though they were still used for fireworks
displays, and a German fireworks maker, Johann Schmidlap, invented the
"step rocket," a multi-staged vehicle for lifting fireworks to higher altitudes.
A large sky rocket (first stage) carried a smaller sky rocket (second stage).
When the large rocket burned out, the smaller one continued to a higher
altitude before showering the sky with glowing cinders. Schmidlap's idea
is basic to all rockets today that go into outer space.
Nearly all uses up to this time were
for warfare or fireworks, but there is an interesting old Chinese legend
that reported the use of rockets as a means of transportation. With the
help of many assistants, a lesser-known Chinese official named Wan-Hu assembled
a rocket- powered flying chair. Attached to the chair were two large kites,
and fixed to the kites were forty- seven fire-arrow rockets.
 On
the day of the flight, Wan-Hu sat himself on the chair and gave the command
to light the rockets. Forty-seven rocket assistants, each armed with torches,
rushed forward to light the fuses. In a moment, there was a tremendous
roar accompanied by billowing clouds of smoke. When the smoke cleared,
Wan-Hu and his flying chair were gone. No one knows for sure what happened
to Wan-Hu, but it is probable that if the event really did take place,
Wan-Hu and his chair were blown to pieces. Fire-arrows were as apt to explode
as to fly.
Next
page > Rocketry Becomes A Science
and The First Modern Designs
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