# Catapult

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A catapult is a ballistic device used to launch a projectile a great distance without the aid of explosive devices—particularly various types of ancient and medieval siege engines. [1] In use since ancient times, the catapult has proven to be one of the most effective mechanisms during warfare. In modern times the term can apply to devices ranging from a simple hand-held implement (also called a "slingshot") to a mechanism for launching aircraft from a ship.

Ballistics is the field of mechanics that deals with the launching, flight, behavior, and effects of projectiles, especially bullets, unguided bombs, rockets, or the like; the science or art of designing and accelerating projectiles so as to achieve a desired performance.

A projectile is any object thrown into space by the exertion of a force. Although any object in motion through space may be called a projectile, the term more commonly refers to a ranged weapon. Mathematical equations of motion are used to analyze projectile trajectory. An object projected at an angle to the horizontal has both the vertical and horizontal components of velocity. The vertical component of the velocity on the y-axis given as Vy=USin(teta) while the horizontal component of the velocity Vx=UCos(teta). There are various terms used in projectiles at specific angle teta 1. Time to reach maximum height. It is symbolized as (t), which is the time taken for the projectile to reach the maximum height from the plane of projection. Mathematically, it is give as t=USin(teta)/g Where g=acceleration due to gravity(app 10m/s²) U= initial velocity (m/s) teta= angle made by the projectile with the horizontal axis.

A siege engine is a device that is designed to break or circumvent heavy castle doors, thick city walls and other fortifications in siege warfare. Some are immobile, constructed in place by sappers to attack enemy fortifications from a distance, while others have wheels to enable advancing up to the enemy fortification. There are many distinct types, such as siege towers to allow attacking soldiers to scale walls and attack the defenders, battering rams to break walls or gates, to catapults, ballistae, trebuchets and other similar constructions used to attack from a distance and fire a projectile; some complex siege engines were combinations of these types.

## Etymology

The word 'catapult' comes from the Latin 'catapulta', which in turn comes from the Greek Ancient Greek : καταπέλτης [2] (katapeltēs), itself from κατά (kata), "downwards" [3] and πάλλω (pallō), "to toss, to hurl". [4] [5] Catapults were invented by the ancient Greeks [6] [7] and in ancient India where they were used by the Magadhan Emperor Ajatshatru around the early to mid 5th century BCE. [8]

Latin is a classical language belonging to the Italic branch of the Indo-European languages. The Latin alphabet is derived from the Etruscan and Greek alphabets, and ultimately from the Phoenician alphabet.

Greek is an independent branch of the Indo-European family of languages, native to Greece, Cyprus and other parts of the Eastern Mediterranean and the Black Sea. It has the longest documented history of any living Indo-European language, spanning more than 3000 years of written records. Its writing system has been the Greek alphabet for the major part of its history; other systems, such as Linear B and the Cypriot syllabary, were used previously. The alphabet arose from the Phoenician script and was in turn the basis of the Latin, Cyrillic, Armenian, Coptic, Gothic, and many other writing systems.

Magadha was an ancient Indian kingdom in southern Bihar, and was counted as one of the sixteen Mahajanapadas of ancient India. Magadha played an important role in the development of Jainism and Buddhism, and two of India's greatest empires, the Maurya Empire and Gupta Empire, originated in Magadha.

## Greek and Roman catapults

The catapult and crossbow in Greece are closely intertwined. Primitive catapults were essentially "the product of relatively straightforward attempts to increase the range and penetrating power of missiles by strengthening the bow which propelled them". [9] The historian Diodorus Siculus (fl. 1st century BC), described the invention of a mechanical arrow-firing catapult (katapeltikon) by a Greek task force in 399 BC. [10] [11] The weapon was soon after employed against Motya (397 BC), a key Carthaginian stronghold in Sicily. [12] [13] Diodorus is assumed to have drawn his description from the highly rated [14] history of Philistus, a contemporary of the events then. The introduction of crossbows however, can be dated further back: according to the inventor Hero of Alexandria (fl. 1st century AD), who referred to the now lost works of the 3rd-century BC engineer Ctesibius, this weapon was inspired by an earlier foot-held crossbow, called the gastraphetes , which could store more energy than the Greek bows. A detailed description of the gastraphetes, or the "belly-bow", [15] [ page needed ] along with a watercolor drawing, is found in Heron's technical treatise Belopoeica. [16] [17]

A crossbow is a type of elastic ranged weapon in similar principle to a bow, consisting of a bow-like assembly called a prod, mounted horizontally on a main frame called a tiller, which is handheld in a similar fashion to the stock of a long gun. It shoots arrow-like projectiles called bolts or quarrels. The medieval European crossbow was called by many other names, most of which were derived from the word ballista, an ancient Greek torsion siege engine similar in appearance.

Diodorus Siculus or Diodorus of Sicily was a Greek historian. He is known for writing the monumental universal history Bibliotheca historica, much of which survives, between 60 and 30 BC. It is arranged in three parts. The first covers mythic history up to the destruction of Troy, arranged geographically, describing regions around the world from Egypt, India and Arabia to Greece and Europe. The second covers the Trojan War to the death of Alexander the Great. The third covers the period to about 60 BC. Bibliotheca, meaning 'library', acknowledges that he was drawing on the work of many other authors.

Carthage was a Phoenician state that included, during the 7th–3rd centuries BC, its wider sphere of influence known as the Carthaginian Empire. The empire extended over much of the coast of Northwest Africa as well as encompassing substantial parts of coastal Iberia and the islands of the western Mediterranean Sea.

A third Greek author, Biton (fl. 2nd century BC), whose reliability has been positively reevaluated by recent scholarship, [11] [18] [ page needed ] described two advanced forms of the gastraphetes, which he credits to Zopyros, an engineer from southern Italy. Zopyrus has been plausibly equated with a Pythagorean of that name who seems to have flourished in the late 5th century BC. [19] [lower-alpha 1] He probably designed his bow-machines on the occasion of the sieges of Cumae and Milet between 421 BC and 401 BC. [22] [23] The bows of these machines already featured a winched pull back system and could apparently throw two missiles at once. [13]

Taranto is a coastal city in Apulia, Southern Italy. It is the capital of the Province of Taranto and is an important commercial port as well as the main Italian naval base.

Pythagoreanism originated in the 6th century BC, based on the teachings and beliefs held by Pythagoras and his followers, the Pythagoreans. Pythagoras established the first Pythagorean community in Crotone, Italy. Early-Pythagorean communities lived throughout Magna Graecia. Espousing a rigorous life of the intellect and strict rules on diet, clothing and behavior comprised a cult of following Pythagorean's Code. Peculiar, the Code's diet, prohibits the consumption or even touching any sort of bean or legume. Pythagoras’ death and disputes about his teachings led to the development of two philosophical traditions within Pythagoreanism. The practitioners of akousmatikoi were superseded in the 4th century BC as a significant mendicant school of philosophy by the Cynics. The Pythagorean mathēmatikoi philosophers were in the 4th century BC absorbed into the Platonic school.

Philo of Byzantium provides probably the most detailed account on the establishment of a theory of belopoietics (belos = "projectile"; poietike = "(art) of making") circa 200 BC. The central principle to this theory was that "all parts of a catapult, including the weight or length of the projectile, were proportional to the size of the torsion springs". This kind of innovation is indicative of the increasing rate at which geometry and physics were being assimilated into military enterprises. [15] [ page needed ]

From the mid-4th century BC onwards, evidence of the Greek use of arrow-shooting machines becomes more dense and varied: arrow firing machines (katapaltai) are briefly mentioned by Aeneas Tacticus in his treatise on siegecraft written around 350 BC. [13] An extant inscription from the Athenian arsenal, dated between 338 and 326 BC, lists a number of stored catapults with shooting bolts of varying size and springs of sinews. [24] The later entry is particularly noteworthy as it constitutes the first clear evidence for the switch to torsion catapults which are more powerful than the flexible crossbows and came to dominate Greek and Roman artillery design thereafter. [25] This move to torsion springs was likely spurred by the engineers of Philip II of Macedonia. [15] [ page needed ] Another Athenian inventory from 330 to 329 BC includes catapult bolts with heads and flights. [24] As the use of catapults became more commonplace, so did the training required to operate them. Many Greek children were instructed in catapult usage, as evidenced by "a 3rd Century B.C. inscription from the island of Ceos in the Cyclades [regulating] catapult shooting competitions for the young". [15] Arrow firing machines in action are reported from Philip II's siege of Perinth (Thrace) in 340 BC. [26] At the same time, Greek fortifications began to feature high towers with shuttered windows in the top, which could have been used to house anti-personnel arrow shooters, as in Aigosthena. [27] Projectiles included both arrows and (later) stones that were sometimes lit on fire. Onomarchus of Phocis first used catapults on the battlefield against Philip II of Macedon. [28] Philip's son, Alexander the Great, was the next commander in recorded history to make such use of catapults on the battlefield [29] as well as to use them during sieges. [30]

Aeneas Tacticus was one of the earliest Greek writers on the art of war and is credited as the first author to provide a complete guide to securing military communications. Polybius described his design for a hydraulic semaphore system.

Athens is the capital and largest city of Greece. Athens dominates the Attica region and is one of the world's oldest cities, with its recorded history spanning over 3,400 years and its earliest human presence starting somewhere between the 11th and 7th millennium BC.

In the field of solid mechanics, torsion is the twisting of an object due to an applied torque. Torsion is expressed in either the Pascal (Pa), an SI unit for newtons per square metre, or in pounds per square inch (psi) while torque is expressed in newton metres (N·m) or foot-pound force (ft·lbf). In sections perpendicular to the torque axis, the resultant shear stress in this section is perpendicular to the radius.

The Romans started to use catapults as arms for their wars against Syracuse, Macedon, Sparta and Aetolia (3rd and 2nd centuries BC). The Roman machine known as an arcuballista was similar to a large crossbow. [31] [32] [33] Later the Romans used ballista catapults on their warships.

## Other ancient catapults

Ajatshatru is recorded in Jaina texts as having used catapults in his campaign against the Licchavis. [34]

King Uzziah, who reigned in Judah until 750 BC, is documented as having overseen the construction of machines to "shoot great stones" in 2Chronicles

## Medieval catapults

Castles and fortified walled cities were common during this period and catapults were used as siege weapons against them. As well as their use in attempts to breach walls, incendiary missiles, or diseased carcasses or garbage could be catapulted over the walls.

Defensive techniques in the Middle Ages progressed to a point that rendered catapults largely ineffective. The Viking siege of Paris (885–6 A.D.) "saw the employment by both sides of virtually every instrument of siege craft known to the classical world, including a variety of catapults", to little effect, resulting in failure. [9]

The most widely used catapults throughout the Middle Ages were as follows: [35]

Ballista
Ballistae were similar to giant crossbows and were designed to work through torsion. The projectiles were large arrows or darts made from wood with an iron tip. These arrows were then shot "along a flat trajectory" at a target. Ballistae were accurate, but lacked firepower compared with that of a mangonel or trebuchet. Because of their immobility, most ballistae were constructed on site following a siege assessment by the commanding military officer. [35]
Springald
The springald's design resembles that of the ballista, being a crossbow powered by tension. The springald's frame was more compact, allowing for use inside tighter confines, such as the inside of a castle or tower, but compromising its power. [35]
Mangonel
This machine was designed to throw heavy projectiles from a "bowl-shaped bucket at the end of its arm". Mangonels were mostly used for “firing various missiles at fortresses, castles, and cities,” with a range of up to 1300 feet. These missiles included anything from stones to excrement to rotting carcasses. Mangonels were relatively simple to construct, and eventually wheels were added to increase mobility. [35]
Onager
Mangonels are also sometimes referred to as Onagers. Onager catapults initially launched projectiles from a sling, which was later changed to a "bowl-shaped bucket". The word Onager is derived from the Greek word onagros for "wild ass", referring to the "kicking motion and force" [35] that were recreated in the Mangonel's design. Historical records regarding onagers are scarce. The most detailed account of Mangonel use is from “Eric Marsden's translation of a text written by Ammianus Marcellius in the 4th Century AD” describing its construction and combat usage. [36]
Trebuchet
Trebuchets were probably the most powerful catapult employed in the Middle Ages. The most commonly used ammunition were stones, but "darts and sharp wooden poles" could be substituted if necessary. The most effective kind of ammunition though involved fire, such as "firebrands, and deadly Greek Fire". Trebuchets came in two different designs: Traction, which were powered by people, or Counterpoise, where the people were replaced with "a weight on the short end". [35] The most famous historical account of trebuchet use dates back to the siege of Stirling Castle in 1304, when the army of Edward I constructed a giant trebuchet known as Warwolf, which then proceeded to "level a section of [castle] wall, successfully concluding the siege". [36]
Couillard
A simplified trebuchet, where the trebuchet's single counterweight is split, swinging on either side of a central support post.
Leonardo da Vinci's catapult
Leonardo da Vinci sought to improve the efficiency and range of earlier designs. His design incorporated a large wooden leaf spring as an accumulator to power the catapult.[ citation needed ] Both ends of the bow are connected by a rope, similar to the design of a bow and arrow. The leaf spring was not used to pull the catapult armature directly, rather the rope was wound around a drum. The catapult armature was attached to this drum which would be turned until enough potential energy was stored in the deformation of the spring. The drum would then be disengaged from the winding mechanism, and the catapult arm would snap around.[ citation needed ] Though no records exist of this design being built during Leonardo's lifetime, contemporary enthusiasts have reconstructed it.[ citation needed ]

## Modern use

### Military

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. They were eventually replaced by small mortars.

In the 1840s the invention of vulcanized rubber allowed the making of small hand-held catapults, either improvised from Y-shaped sticks or manufactured for sale; both were popular with children and teenagers. These devices were also known as slingshots in the USA.

Special variants called aircraft catapults are used to launch planes from land bases and sea carriers when the takeoff runway is too short for a powered takeoff or simply impractical to extend. Ships also use them to launch torpedoes and deploy bombs against submarines.[ dubious ] Small catapults, referred to as "traps", are still widely used to launch clay targets into the air in the sport of clay pigeon shooting.

### Entertainment

In the 1990s and into the early 2000s, a powerful catapult, a trebuchet, was used by thrill-seekers first on private property and in 2001-2002 at Middlemoor Water Park, Somerset, England to experience being catapulted through the air for 100 feet (30 m). The practice has been discontinued due a fatality at the Water Park. There had been an injury when the trebuchet was in use on private property. Injury and death occurred when those two participants failed to land onto the safety net. [37] The operators of the trebuchet were tried, but found not guilty of manslaughter, though the jury noted that the fatality might have been avoided had the operators "imposed stricter safety measures." [38] [39] Human cannonball circus acts use a catapult launch mechanism, rather than gunpowder, and are risky ventures for the human cannonballs. [40]

Early launched roller coasters used a catapult system powered by a diesel engine or a dropped weight to acquire their momentum, [41] such as Shuttle Loop installations between 1977-1978. The catapult system for roller coasters has been replaced by flywheels and later linear motors.

Pumpkin chunking is another widely popularized use, in which people compete to see who can launch a pumpkin the farthest by mechanical means (although the world record is held by a pneumatic air cannon).

### Other

In January 2011, a homemade catapult was discovered that was used to smuggle cannabis into the United States from Mexico. The machine was found 20 feet from the border fence with 4.4 pounds (2.0 kg) bales of cannabis ready to launch. [42]

## Notes

1. Lewis established a lower date of no later than the mid-4th century. [20] So did de Camp. [21]

## Related Research Articles

The ballista, plural ballistae, sometimes called bolt thrower, was an ancient missile weapon that launched a large projectile at a distant target.

A trebuchet is a type of catapult, a common and powerful type of siege engine which uses a swinging arm to throw a projectile.

A mangonel, also called the traction trebuchet, was a type of trebuchet or siege engine used in China starting from the Warring States period, and later across Eurasia in the 6th century AD. Unlike the earlier torsion engines and later counterweight trebuchet, the mangonel operated on manpower pulling cords attached to a lever and sling to launch projectiles. Although the mangonel required more men to function, it was also less complex and faster to reload than the torsion powered ballista and onager which it replaced in early Medieval Europe.

The onager was an imperial-era Roman torsion powered siege engine; in other words, a small catapult. The onager was first mentioned in 353 AD by Ammianus Marcellinus, who described onagers as the same as a scorpion.

Early thermal weapons were devices or substances used in warfare during the classical and medieval periods which used heat or burning action to destroy or damage enemy personnel, fortifications or territories.

A ranged weapon is any weapon that can engage targets beyond hand-to-hand distance, i.e. at distances greater than the physical reach of the weapon itself. It is sometimes also called projectile weapon or missile weapon because it typically works by launching projectiles, though technically a directed-energy weapon is also a ranged weapon. In contrast, a weapon intended to be used in hand-to-hand combat is called a melee weapon.

Roman siege engines were, for the most part, adapted from Hellenistic siege technology. Relatively small efforts were made to develop the technology; however, the Romans brought an unrelentingly aggressive style to siege warfare that brought them repeated success. Up to the first century BC, the Romans utilized siege weapons only as required and relied for the most part on ladders, towers and rams to assault a fortified town. Ballistae were also employed, but held no permanent place within a legion's roster, until later in the republic, and were used sparingly. Julius Caesar took great interest in the integration of advanced siege engines, organizing their use for optimal battlefield efficiency.

The gastraphetes was a hand-held crossbow used by the Ancient Greeks. It was described in the 1st century AD by the Greek author Heron of Alexandria in his work Belopoeica, which draws on an earlier account of the famous Greek engineer Ctesibius. Heron identifies the gastraphetes as the forerunner of the later catapult, which places its invention some unknown time prior to c. 420 BC.

A lithobolos refers to any mechanical artillery weapon used and/or referred to as a stone thrower in ancient warfare. Typically this referred to engines that propel at stone along a flat track with two rigid bow arms powered by torsion, in particular all sizes of palintonon.

Petrary is a generic term for a medieval stone-throwing siege engine, used to hurl large rocks against the walls of the besieged city, in an attempt to break down the wall and create an entry point.

The scorpio or scorpion was a type of Roman torsion siege engine and field artillery piece. It was described in detail by the early-imperial Roman architect and engineer Vitruvius in the 1st century BC and by the 4th century AD officer and historian Ammianus Marcellinus.

It is not clear where and when the crossbow originated, but it is believed to have appeared in China and Europe around the 7th to 5th centuries BC. In China the crossbow was one of the primary military weapons from the Warring States period until the end of the Han dynasty, when armies composed of up to 30 to 50 percent crossbowmen were not unheard of. The crossbow lost much of its popularity after the fall of the Han dynasty. One Tang dynasty source recommends a bow to crossbow ratio of five to one as well as the utilization of the countermarch to make up for the crossbow's lack of speed. The crossbow countermarch technique was further refined in the Song dynasty, but crossbow usage in the military continued to decline after the Mongol conquest of China. Although the crossbow never regained the prominence it once had under the Han, it was never completely phased out either. Even as late as the 17th century, military theorists were still recommending it for wider military adoption, but production had already shifted in favor of firearms and traditional composite bows.

A torsion siege engine is a type of artillery that utilizes torsion to launch projectiles. They were initially developed by the ancient Greeks, specifically Philip II of Macedon and Alexander the Great, and used through the Middle Ages until the development of gunpowder artillery in the 14th century rendered them obsolete.

Throughout history, people have used weapons in warfare, hunting, self-defense, law enforcement, and criminal activity. Weapons also serve many other purposes in society including use in sports, collections for display, and historical displays and demonstrations. As technology has developed throughout history, weapons have changed with it.

Petraria Arcatinus is a possibly fictitious catapult which is claimed to have been in use during the Middle Ages. The name appears in some non-scholarly modern texts and websites. It is often roughly translated as "bow-powered stone-thrower". Modern depictions of this catapult are usually of an onager with its torsion spring power source replaced by a bow, but some doubt if this weapon ever existed.

The Greeks and Romans both made extensive use of artillery for shooting large arrows or rocks.

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