catapults

Catapults are siege engines using an arm to hurl a projectile a great distance. Any machine that hurls an object can be considered a catapult, but the term is generally understood to mean medieval siege weapons.

The name is derived from the Greek κατα (against) and βαλλειν (to hurl (a missile)). Originally, "catapult" referred to a stone-thrower, while "ballista" referred to a dart-thrower, but the two terms swapped meaning sometime in the fourth century AD.

Catapults were usually assembled at the site of a siege, and an army carried few or no pieces of it with them because wood was easily available on site. Catapults can be classified according to the physical concept used to store and release the energy required to propel the projectile

Types

Catapults can be classified according to the physical concept used to store and release the energy required to propel the projectile.

The first catapult distinct from hand-held launchers (bows, crossbows, slings etc.) was the Greek gastrophetes, a crossbow so large it was braced against the abdomen rather than being held in the hand, hence the nickname belly-bow. The next step from this was a larger form a crossbow mounted on a stand, including early versions of the oxybeles (Greek for bolt shooter) and the ballista (the Roman version of the oxybeles). The arbalette à tour was a medieval version of the stand-mounted crossbow. These catapults are tensional, in that the energy is stored as tension and compression of the bow. Although similar to a crossbow, a sling on the end of the rope meant these weapons could be used for firing all sorts of projectiles, from rocks to pots of Greek fire.

Subsequently, torsional catapults were developed; those with two torsion powered arms, the later versions of the ballista and oxybeles, and those with one torsion powered arm, the onager, known in medieval times as the mangonel. The bottom end of the throwing arm of the onager and the inner ends of both ballista arms are inserted into rope or fibers that are twisted, providing a torsional store of energy. Torsional ballistas were operationally equivalent to their tensional cousins, except the torsional energy store gave greater power. Onagers have an arm with a bucket, cup, or most often a sling to hold the projectile at one end.

Finally, the last type of catapult is a trebuchet, which used gravity or traction rather than tension or torsion to propel the throwing arm. A falling counterweight, or the effort of the one or more operators, pull down the bottom end of the arm and the projectile is thrown from a sling attached to a rope hanging from the top end of the arm, essentially like a sling attached to a giant see-saw. The counterweight was usually much heavier than the projectile. More modern trebuchets often replace the counterweight with industrial springs to create tension (Video).

History

In Europe, the first catapults appeared in later Greek times around 400 BC-300 BC ^{citations needed]}. According to Roman engineer Heron of Alexandria, the first types derived from by the earlier gastraphētes ("Belly shooter"), constisting in camposite bow mounted trasversely on a stock. Biton attributes the creation of the first crewed catapult to one Zopyrus from Taranto, in soutern Italy.

Early adopters of the catapult design were Dionysius of Syracuse (who called it katapeltikon) and Onomarchus of Phocis. Katapaltai are mentioned in the Siegecraft (Poliorkētika) treatise of Aeneas Tacticus, from around 350 BC. It is probable that standard torsion-powered catapults entered in common use in Greek world and Macedon only around 330 BC. Alexander the Great introduced the idea of using them to provide cover on the battlefield in addition to using them during sieges. Projectiles included both arrows and (later) stones.

Romans started to use catapults probably as booty from their wars against Syracuse, Macedon, Sparta and Aetolia (3rd-2nd century BC). Standard use of artillery (ballista and onager) is attested only from the time of Julius Casear, however.

In the Medieval times, when the trebuchet was introduced a relatively short time before the advent of gunpowder, the catapult became basically obsolete. Cannons soon replaced catapults as the standard siege weapon in Europe in the 14th century.

During medieval times, catapults and related siege machines were the first weapons used for biological warfare. The carcasses of diseased animals and those who had perished from the Black Death or other diseases were loaded onto the catapult and then thrown over the castle's walls to infect those barricaded inside. There have even been recorded instances of beehives being catapulted over castle walls.

The last large-scale military use of catapults was during the trench warfare of World War I. During the early stages of the war, catapults were used to throw hand grenades across no man's land into enemy trenches.

At the present, in England, trebuchets are sometimes used by thrill-seekers as human catapults to experience being catapulted through the air. There has been at least one fatality, when the participant failed to land onto the safety net.

See also

• siege engine, or — Medieval siege weaponry
• Onager (siege weapon)
• Trebuchet
• Slingshot
• Aircraft catapult
• Mass driver
• Ballista

External links

• Sunward Aerospace, feature a working Catapult Model Kit
• [1], offers catapults for science projects and engineering courses on experimentation (commercial site)
• Catapult Plans and Design
• Medieval Catapult Articles
• Chinese Siege Warfare: Mechanical Artillery & Siege Weapons of Antiquity - An Illustrated History
• Video of Spring Trebuchet in Action
• A modern slinging catapult for competition & entertainment, features photos and videos of a pumpkin hurling and appliance tossing catapult

References

• The Compact Edition of the Oxford English Dictionary (1971)