Composite bows

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A composite bow is a bow made from disparate materials laminated together, usually applied under tension. Different materials are used in order to take advantage of the properties of each material.

This article describes mainly the traditional Asiatic composite bow, which normally uses horn on the belly and sinew on the back of a wooden core. Sinew and horn will store more energy than wood for the same length of bow. The strength can be made similar to that of all-wood bows, with similar draw-length and therefore a similar or greater amount of energy delivered to the arrow from a much shorter bow. Some Mongolian composite bows are known to have been able to produce a draw weight of nearly 160 lb (72.5 Kg).


Advantages and disadvantages

Advantages

The main advantage of composite bows over self bows (made from a single piece of wood) is their combination of smaller size with high power. They are therefore much more suitable for use from horseback, and presumably from a chariot. Almost all composite bows are also recurve bows as the shape curves back away from the archer; this design gives higher draw-weight in the early stages of the archer's draw, so storing somewhat more total energy for a given final draw-weight. It would be possible to make a bow of wood that has the same shape, length and draw-weight as a traditional composite bow, but it could not store the energy and would break at full draw.


Disadvantages

Constructing composite bows requires much more time and a greater variety of materials than self bows, and the animal glue traditionally used can lose strength in humid conditions and be quickly ruined by submersion. For most practical non-mounted archery purposes, composite construction offers no advantage; "the initial velocity is about the same for all types of bow... within certain limits, the design parameters... appear to be less important than is often claimed." However, they are superior for horsemen and in the specialized art of flight archery: "A combination of many technical factors made the composite flight bow better for flight shooting."


Materials

Water buffalo horn is very suitable, as is horn of several antelopes such as gemsbok, oryx, ibex, and that of Hungarian grey cattle. Goat and sheep horn can also be used. Most forms of cow horn are not suitable, as they soon break up in use.

The wooden core is not normally under severe mechanical stress, and a wide variety of lighter woods should be suitable. The wood needs to accept glue well. Bamboo and wood of the mulberry family are traditional in China.

The sinew is normally obtained from the lower legs and back of wild deer or domestic ungulates. Traditionally, ox tendons are considered inferior to wild-game sinews since they have a higher fat content, leading to spoilage.

Hide glue or gelatin made from fish gas bladders is used to attach layers of sinew to the back of the bow. Traditionally it is also used to attach the horn belly to the wooden core.

Other less-satisfactory materials than horn have been used for the belly of the bow (the part facing the archer when shooting), including bone, antler, or compression resistant woods such as osage orange, hornbeam, or yew. Materials that are strong under tension, such as silk, or tough wood like hickory, have been used on the back of the bow (the part facing away from the archer when shooting)


History

Origins, working tips

Bows of any kind seldom survive in the archaeological record. Composite bows may have been invented first by the nomads of the Asiatic steppe, who may have based it on earlier Northern Asian laminated bows. However, archaeological investigation of the Asiatic steppe is still limited and patchy, and it is not possible to reconstruct the details of the process by which composite bows became a usual weapon among all Asiatic nomads. It is also not clear that the various developments of the composite bow led to measurable improvements; "the development of archery equipment may not be a process involving progressive improvements in performance. Rather, each design type represents one solution to the problem of creating a mobile weapon system capable of hurling lightweight projectiles."

The first appearance of composite bows coincides approximately with the adoption of the horse to draw chariots or as a riding animal. Variants of the Scythian bow were the dominant form for millennia in the area between China and Europe. These were short weapons - one was 119 cm long when strung, with arrows perhaps 50-60 cm long - with working tips. Composite bows were soon adopted and adapted by civilizations, such as the Chinese, Assyrian, Indian, and Egyptian, who came into contact with nomads. Several composite bows were found in the tomb of Tutankhamun, who died in 1324 BCE. Composite bows are known in China from at least the Warring States Period. The military of the Han Dynasty (220 BCE-206 CE) utilized composite crossbows, often in infantry square formations, in their many engagements against the Xiongnu. Horse archers such as the Scythians, Parthians, Huns, Bulgars, Seljuk Turks, and Mongols often used skirmishing tactics where they would approach, shoot, and retreat. The term Parthian shot refers to the widespread horse-archer tactic of shooting backwards over the rear of their horses as they retreated.

Aryan nomads such as Scythians, Sakas, and Sarmatians were skilled horse archers. Parthians, originally a Scythian tribe, were famed horse archers. Parthians inflicted several devastating defeats on Romans, the first being the Battle of Carrhae. However, horse archers were not invincible; Han General Ban Chao led successful military expeditions against these nomads in the late 1st century CE that conquered as far as central Asia, and Alexander the Great may be the only general who inflicted a defeat on horse archer armies on his first contact with them.

Siyahs, stiff tips

Later, it became usual to stiffen the ends of composite bows. The stiffened ends of the bows are "siyahs". For centuries, the stiffening was accomplished by attaching laths of bone or antler to the sides of the bow at its ends. The bone or antler strips are more likely to survive burial than the rest of the bow. The first bone strips suitable for this purpose come from "graves of the fourth or third centuries" BCE. These stiffeners are found associated with nomads of the time, such as the Alans and Huns, whose ancestors may have invented them. Maenchen-Helfen states that they are not found in Achaemenid Persia, nor in early Imperial Rome, nor in Han China. However Coulston attributes Roman stiffeners to about or before 9 CE. He identifies a Steppe Tradition of Scythian bows with working tips, which lasted, in Europe, until the arrival of the Huns, and a Near East or Levantine tradition with siyahs, possibly introduced by the Parni as siyahs are found in Sassanid but not Achaemenid contexts. They have also been described from the Arabian peninsula. They were adopted by the Roman Empire and were made even in the cold and damp of Britannia. They were the normal weapon of later Roman archers, both infantry and cavalry units (although Vegetius recommends training recruits "arcubus ligneis", with wooden bows, which may have been made in the northern European longbow tradition.)

With the arrival of the Huns, a separate tradition of bows with siyahs arrived in Europe. "Rausing termed it the 'Qum-Darya Bow' from the Han Chinese type-site at the frontier post of Lou-lan, at the mouth of the (Qum-Darya) river, dated by analogy to c. 1st century B.C. to 3rd century A.D. Fittings from this type of bow appear right across Asia from Korea to the Crimea. Alanic graves in the Volga region dating to the 3rd to 4th century A.D. signal the adoption of the Qum-Darya type by Sarmatian peoples from Hunnic groups advancing from the East. In general, Hunnic/Qum-Darya bows had two pairs of ear laths identical in every respect to those found on Roman limes sites. The only difference is that there are proportionally a greater number of longer laths (like those Roman examples from Bar Hill and London). In addition the grip of the bow was stiffened by three laths. On the sides were glued a pair of trapezoidal laths with their longest edges towards the back. On the belly was glued a third lath, varying in shape but often narrow with parallel sides and splayed ends. Therefore, each bow possessed seven grip and ear laths, compared with none on the Scythian and Sarmatian bows and four (ear) laths on the Yrzi bow."

Such bows may usually have been asymmetric, with lower limbs shorter than the upper.To some extent, this combines the power of a longer bow with the convenience of a shorter one.

The Huns and their successors greatly impressed their neighbours with their archery. Germanic tribes transmitted their respect orally for a millennium; in the Scandinavian Hervarar saga, the Geatish king Gizur taunts the Huns and says, "Eigi gera Húnar oss felmtraða né hornbogar yðrir." (We fear neither the Huns nor their hornbows.) The Romans were so impressed with Hunnic tactics that, as described in the Strategikon, Procopius's histories, and other works, they changed the entire emphasis of their army, from heavy infantry to cavalry, many of them armed with bows.

After the fall of the Western empire, Eastern Roman armies maintained their tradition of horse archery for centuries. They finally fell to the Turks before the decline of military archery in favour of guns. Turkish armies included archers until about 1591 (they played a major role in the Battle of Lepanto (1571), though they were defeated by the firearms-wielding Christians), and flight archery remained a popular sport in Istanbul until the early 1800s.

Integral wooden siyahs

Later developments in the composite bow included siyahs made as a continuation of the wooden core of the bow, rather than strengthened by external reinforcement.


String bridges

A string "bridge" or "run" is an attachment of horn or wood, used to hold the string a little further apart from the bow's limbs at the base of the siyahs. This attachment adds weight, but might give a small increase in the speed of the arrow by increasing the initial string angle and therefore the force of the draw in its early stages. This feature is characteristic of recent Mongolian and Chinese bows, but it is not shown in artwork from the time of Genghis Khan's conquests or the succeeding Ming Dynasty. String bridges were a later adoption from the Manchurian (Qing dynasty) bows of northwestern China.

Most surviving documentation of the use and construction of composite bows comes from China and the Middle East; until reforms early in the 20th century, skill with the composite bow was an essential part of the qualification for officers in the Chinese Imperial army.


Modern "composite" bows

Modern replicas of traditional composite bows are commercially available; they are usually made with fibreglass on both belly and back, easier to mass-produce and easier to take care of than traditional composite bows.


American composite bows

When Europeans first contacted Native Americans, some bows, especially in the area that became California, already had sinew backing. After the reintroduction of horses, newly mounted groups rapidly developed shorter bows, which were often given sinew backing. The full three-layer composite bow with horn, wood, and sinew does not seem to be recorded in the Americas, and horn bows with sinew backing are not recorded before European contact.


Types of composite bow

All Eurasian composite bows derive from the same nomad origins, but every culture that used them has made its own adaptations to the basic design. The Turkish, Mongolian, and Korean bows were standardized when archery lost its military function and became a popular sport. Recent Turkish bows are optimized for flight shooting.


Chinese bow

Zhangxian shooting a pebble bow.The Chinese archery tradition goes back millennia. There is also a long tradition of local developments. The modern Chinese and Mongolian bows are similar to each other, both having string bridges derived from the Manchurian tradition.


Mongol bow

The Mongolian tradition of archery is attested by an inscription on a stone stele that was found near Nerchinsk in Siberia: "While Genghis Khan was holding an assembly of Mongolian dignitaries, after his conquest of Sartaul (East Turkestan), Yesüngge (the son of Genghis Khan's brother) shot a target at 335 alds (536 m)."

Until today, archery with traditional composite bows is part of the annual festival of the three virile sports (Wrestling, Horseriding, Archery), called "Naadam".


Hungarian bow

The Hungarian bow is a fairly long, approximately symmetrical, composite reflex bow with bone stiffeners. Its shape is known from two graves in which the position of the bone plates could be reconstructed. In general, details of the bows of other ethnic groups in history are known on the basis of similarly scanty evidence.

Korean bow

Main article: Korean bow A traditional modern Korean bow, or gakgung, is a small but very efficient horn-bamboo-sinew composite bow. Korean archers normally practice at a range of approximately 145 metres.


Perso-Parthian bow

The Perso-Parthian bow is a symmetric recurve under high tension when strung. The "arms" of the bow are supposed to reflex far enough to cross each other when the bow is unstrung. The finished bow is covered by bark, fine leather, or in some cases shark skin to keep out moisture.

Perso-Parthian bows were in use as late as 1820s in Persia (ancient Iran). They were then replaced by muskets.

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