Mangonel

A mangonel (derived from Greco-Latin word manganon, meaning "engine of war") was a type of catapult or siege engine used in the medieval period to throw projectiles at a castle's walls. The exact meaning of the term is debatable, and several possibilities have been suggested. Mangonel may also be indirectly referring to the mangon, a French hard stone found in the south of France. It may have been a name for counterweight artillery (trebuchets), possibly either a men-assisted fixed-counterweight type, or one with a particular type of frame. The Arabic term manajaniq comes from the same word, and applies to various kinds of trebuchet. It is also possible that it referred to more than one kind of engine, in different times or places, or was a general term.

In modern parlance, catapult is often used as the name of a medieval form of onager, though there is little evidence for this historically. In this sense, mangonel had poorer accuracy than a trebuchet (which was introduced later, shortly before the discovery and widespread usage of gunpowder). The mangonel threw projectiles on a lower trajectory and at a higher velocity than the trebuchet, with the intention of destroying walls, rather than hurling projectiles over them. It was more suited to field battles.

Role in war
Traction trebuchets (which may be what are referred to as mangonels in medieval sources) were beam-sling weapons, similar to trebuchets. They hurled rocks, burning objects (fire pots, vessels filled with flammable materials that created a fireball on impact), or anything else readily available to the attacking and defending forces. The more unusual types of projectile included dead (and often partially decomposed) carcasses of animals or people (and even human heads), used to intimidate, demoralize, and spread disease among the besieged. This tactic often proved effective. The short supply of food, which was often of low quality or rotting, combined with the cramped living space of the defenders, poor hygiene, and vermin infestations provided an ideal scenario for the spread of disease. It should be noted, however, that the medieval mangonel's principal role in war was in siege warfare, to damage a castle or city's walls and infrastructure, or to harm or harass defending troops.

Popular depictions of onager-like mangonels often show them shooting heavy projectiles from a bowl-shaped bucket at the end of the arm. This arrangement might suit a wider range of projectiles, but would be much less powerful than a weapon fitted with a sling.

Middle ages
The mangonel in the Middle Ages had a different connotation from the Roman onager. It was more similar to the counterweight-powered trebuchet; the primary difference was that the pulling power of several men was used instead of the trebuchet's falling counterweight. This way, with trained workers, the leader of the craft could adjust the strength applied to the mangonel. It is possible that hybrid mangonel-trebuchet engines existed, with both pulling men and a falling counterweight.

Working system of the mangonel
The hybrid mangonel-trebuchet might be loaded by lowering a rope with a hook at its end; this hook was tied to another rope connected to a "pulling" system (this could be a pulley compound,a gear compound, or even an animal traction system) to pull the rope and lower the main beam. Once the beam was lowered a few workers were responsible for the attachment of a sling where the projectile was placed. When the mangonel was loaded the leader gave the order to release the main rod, and at the same time several men (usually around 20) pulled the ropes attached to the counterweight.

If the crew was well-trained, it was possible to control whether the projectile traveled in a low or high trajectory, which is set primarily by the fore-aft position of the sling. If the crew was not well-trained then the risk of the projectile killing friendly troops or even the crew itself existed.