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A composite bow is a traditional bow made from horn, wood, and sinew laminated together, cf., laminated bow. The horn is on the belly, facing the archer, and sinew on the outer side of a wooden core. When the bow is drawn, the sinew (stretched on the outside) and horn (compressed on the inside) store more energy than wood for the same length of bow. The strength can be made similar to that of all-wood "self" bows, with similar draw-length and therefore a similar amount of energy delivered to the arrow from a much shorter bow. However, making a composite bow requires more varieties of material than a self bow, its construction takes much more time, and the finished bow is more sensitive to moisture. Composite bows have been known from archaeology and art since the second millennium BCE, but their history is not well recorded as they were developed by cultures without a written tradition. They originated among Asiatic pastoralists who used them as daily necessities, classically for mounted archery although they can also be used on foot. Such bows spread among the military (and hunters) of civilizations that came into contact with nomad tribes; composite bows have been used across Asia from Korea to the Atlantic coasts of Europe and North Africa, and southwards in the Arabian peninsula and in India. The use of horn in a bow was even remarked on in Homer's epic, The Odyssey, believed to have been written in the 8th century BC. The details of manufacture varied between the various cultures that used them. Initially the tips of the limbs were made to bend when the bow was drawn. Later, the tips were stiffened with bone or antler laths; post-classical bows usually have stiff tips, known as ''siyahs'', which are made as an integral part of the wooden core of the bow. Like other bows, they lost importance with the introduction and increasing accuracy of guns. In some areas composite bows were still used and were further developed for leisure purposes. Later Turkish bows are specialized for flight archery (shooting for distance). Composite bows are still made and used in Korea and in China, and the tradition has been revived elsewhere. Modern replicas are available, often made with fiberglass bellies and backs with a natural or man-made core. ==Construction and materials== The wooden core gives the bow its shape and dimensional stability. It is often made of multiple pieces, joined with animal glue in V-splices, so the wood must accept glue well. Pieced construction allows the sharp bends that many designs require, and the use of woods with different mechanical properties for the bending and nonbending sections. The wood of the bending part of the limb (''"dustar"'') must endure intense shearing stress, and denser woods such as hard maples are normally used in Turkish bows. Bamboo, and wood of the mulberry family, are traditional in China. Some composite bows have nonbending tips (''"siyahs"''), which need to be stiff and light; they may be made of woods such as Sitka spruce.〔 * (1992) ''The Traditional Bowyers Bible Volume 1''. The Lyons Press. ISBN 1-58574-085-3 * (1992) ''The Traditional Bowyers Bible Volume 2''. The Lyons Press. ISBN 1-58574-086-1 * (1994) ''The Traditional Bowyers Bible Volume 3''. The Lyons Press. ISBN 1-58574-087-X〕 A thin layer of horn is glued onto what will be the belly of the bow, the side facing the archer. Water buffalo horn is very suitable, as is horn of several antelopes such as gemsbok, oryx, ibex, and that of Hungarian grey cattle.〔(A BRIEF HISTORICAL OVERVIEW OF HUNGARIAN ARCHERY, PART I. Chris Szabó )〕 Goat and sheep horn can also be used. Most forms of cow horn are not suitable, as they soon delaminate with use. The horn can store more energy than wood in compression.〔 The sinew, soaked in animal glue, is then laid in layers on the back of the bow; the strands of sinew are oriented along the length of the bow. 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.〔 Sinew will extend farther than wood, again allowing more energy storage. Hide glue or gelatin made from fish gas bladders is used to attach layers of sinew to the back of the bow, and to attach the horn belly to the wooden core.〔 Stiffening laths, if used, are attached. Both horn and laths may be bound and glued with further lengths of sinew. After months of drying the bow is ready for use. Further finishing may include thin leather or waterproof bark, to protect the bow from moisture, and recent Turkish bows were often highly decorated with colourful paints and gold leaf. Strings and arrows are essential parts of the weapon system, but no type of either is specifically associated with composite bows throughout their history. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Composite bow」の詳細全文を読む スポンサード リンク
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