Bow

A is an elastic launching device used to fire long-shafted projectiles called arrows, at a target. Many different types of bows are used in. The shape of a bow is a cultural matter. What really matters is the bow’s size, which determines its range and accuracy. In general, the larger the bow, the more powerful it is. Bows are generally used as hunting weapons or employed en masse by foot archers to break up enemy formations.

Basic design and use
A bow consists of a semi-rigid but elastic arc with a high-tensile bowstring joining the ends of the two limbs of the bow. An arrow is a projectile with a pointed tip and a long shaft with stabilizer fins called fletching towards the back, with a narrow notch (nock) at the very end to contact the bowstring.

To load an arrow for shooting (nocking an arrow), the archer places an arrow across the middle of the bow with the bowstring in the arrow’s nock. To shoot, the archer pulls back (draws) the arrow and the bowstring, which in turn flexes the bow limbs, storing. Typically while maintaining the draw, the archer sights along the arrow to aim it. Finally the archer releases (looses) the arrow, allowing the limbs’ stored to convert into, which is transmitted via the bowstring to the arrow, propelling it to fly forward with high velocity.

A container or bag for additional arrows for quick reloading is called a .

When not in use, bows are generally kept unstrung, meaning one or both ends of the bowstring are detached from the bow. This removes all residual tension on the bow, and can help prevent it from losing strength or elasticity over time. For many bow designs, this also lets it straighten out more completely, reducing the space needed to store the bow. Returning the bowstring to its ready-to-use position is called stringing the bow.

Parts of the bow
The basic elements of a bow are a pair of curved elastic limbs, traditionally made from wood, joined by a riser. Both ends of the limbs are connected by a string known as the bow string. By pulling the string backwards the archer exerts on the string-facing section, or belly, of the limbs as well as placing the outer section, or back, under tension. While the string is held, this stores the energy later released in putting the arrow to flight. The force required to hold the string stationary at full draw is often used to express the power of a bow, and is known as its draw weight, or weight. All things being equal, a higher draw weight means a more powerful bow, which is able to project heavier arrows at the same velocity or the same arrow at a greater velocity.

The various parts of the bow can be subdivided into further sections. The topmost limb is known as the upper limb, while the bottom limb is the lower limb. At the tip of each limb is a nock, which is used to attach the bowstring to the limbs. The riser is usually divided into the grip, which is held by the archer, as well as the arrow rest and the bow window. The arrow rest is a small ledge or extension above the grip which the arrow rests upon while being aimed. The bow window is that part of the riser above the grip, which contains the arrow rest.

In bows drawn and held by hand, the maximum draw weight is determined by the strength of the archer. The maximum distance the string could be displaced and thus the longest arrow that could be loosed from it, a bow’s draw length, is determined by the size of the archer.

A composite bow uses a combination of materials to create the limbs, allowing the use of materials specialized for the different functions of a bow limb. Typically a composite bow uses wood for lightness and dimensional stability in the core, horn to store energy in compression, and sinew for its ability to store energy in tension. Such bows often use a stiff end on the limb end, having the effect of a recurve.

Bowstrings
Bowstrings may have a nocking point marked on them, which serves to mark where the arrow is fitted to the bowstring before shooting. The area around the nocking point is usually bound with thread to protect the area around the nocking point from wear by the archer’s hands. This section is called the serving. At one end of the bowstring a loop is formed, which is permanent. The other end of the bowstring also has a loop, but this is not permanently formed into the bowstring but is constructed by tying a knot into the string to form a loop. Traditionally this knot is known as the archer’s knot, but is a form of the. The knot can be adjusted to lengthen or shorten the bowstring. The adjustable loop is known as the “tail”. The string is often twisted (this being called the “flemish twist”).

Bowstrings have been constructed of many materials throughout history, including fibres such as flax, silk, and hemp. Other materials used are animal guts, animal sinews, and rawhide.

Types of bow
There is no one accepted system of classification of bows. Bows may be described by various characteristics including the materials used, the length of the draw that they permit, the shape of the bow in sideways view, and the shape of the limb in cross-section.

Commonly-used descriptors for bows include:

By side profile

 * Recurve bow: a bow with the tips curving away from the archer. The curves straighten out as the bow is drawn and the return of the tip to its curved state after release of the arrow adds extra velocity to the arrow.
 * Reflex bow: a bow whose entire limbs curve away from the archer when unstrung. The curves are opposite to the direction in which the bow flexes while drawn.

By material

 * Self bow: a bow made from one piece of wood.
 * Composite bow: a bow made of more than one material.

By cross-section of limb

 * Longbow: a self bow with limbs rounded in cross-section, about the same height as the archer so as to allow a full draw, usually over 5 ft long. On Terra, the traditional English longbow was usually made of yew wood, but other woods are also used.
 * Flatbow: the limbs are approximately rectangular in cross-section. On Terra, this was traditional in many societies and is the most efficient shape for bow limbs.

Other characteristics

 * Takedown bow: a bow that can be demounted for transportation, usually consisting of three parts: two limbs and a riser, in addition to the string.
 * Compound bow: a bow with mechanical aids to help with drawing the bowstring. Usually, these aids are pulleys at the tips of the limbs, and cams to help hold the load while the bow is drawn. Such bows are usually drawn with a, a hook with a trigger for a consistently clean release.
 * Crossbow: a bow mounted horizontally on a frame which has a mechanism for holding the string at full draw. A crossbow shoots a “bolt” or “quarrel”, rather than an arrow.

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