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Scissors are hand-operated shearing instruments. They consist of a pair of metal blades pivoted so that the sharpened edges slide against each other when the handles (bows) opposite to the pivot are closed. Scissors are used for cutting various thin materials, such as paper, cardboard, metal foil, thin plastic, cloth, rope, and wire. Scissors can also be used to cut hair. Hair cutting scissors have a specific blade angle ideal for cutting hair. Using the incorrect scissors to cut hair will result in increased damage and or split ends by breaking the hair. Food scissors, also known as kitchen scissors, are for cutting and trimming foods such as meats. Hair cutting scissors and shears are functionally equivalent, but the larger implements tend to be called shears.
A large variety of scissors and shears exist for different specialized purposes.
The noun "scissors" is treated as a plural noun, and therefore takes a plural verb ("these scissors are"). Alternatively, it is also referred to as "a pair of scissors". In American English, "a pair" is singular and therefore takes a singular verb ("this pair of scissors is"). In other forms of English, "a pair" does not take the singular (so simply "these scissors are"). The word shears is used to describe similar instruments that are larger in size and for heavier cutting. Opinions vary geographically as to the size at which 'scissors' become 'shears', but this is often at between six to eight inches (about 15 to 20 cm) in length.
It is most likely that scissors were invented around 1500 BC in ancient Egypt. The earliest known scissors appeared in Mesopotamia 3,000 to 4,000 years ago. These were of the 'spring scissor' type comprising two bronze blades connected at the handles by a thin, flexible strip of curved bronze which served to hold the blades in alignment, to allow them to be squeezed together, and to pull them apart when released.
Spring scissors continued to be used in Europe until the 16th century. However, pivoted scissors of bronze or iron, in which the blades were pivoted at a point between the tips and the handles, the direct ancestor of modern scissors, were invented by the Romans around AD100. They entered common use not only in ancient Rome, but also in China, Japan, and Korea, and the idea is still used in almost all modern scissors.
During the Middle Ages and Renaissance, spring scissors were made by heating a bar of iron or steel, then flattening and shaping its ends into blades on an anvil. The center of the bar was heated, bent to form the spring, then cooled and reheated to make it flexible.
William Whiteley & Sons (Sheffield) Ltd. was manufacturing scissors by 1760, although it is believed the business began trading even earlier. The first trade-mark, 332, was granted in 1791.
Pivoted scissors were not manufactured in large numbers until 1761, when Robert Hinchliffe produced the first pair of modern-day scissors made of hardened and polished cast steel. He lived in Cheney Square, London and was reputed to be the first person who put out a signboard proclaiming himself "fine scissor manufacturer".
During the 19th century, scissors were hand-forged with elaborately decorated handles. They were made by hammering steel on indented surfaces known as bosses to form the blades. The rings in the handles, known as bows, were made by punching a hole in the steel and enlarging it with the pointed end of an anvil.
In 1649, in Swedish-ruled Finland, an ironworks was founded in the village of Fiskars between Helsinki and Turku. In 1830, a new owner started the first cutlery works in Finland, making, among other items, scissors with the Fiskars trademark. In 1967, Fiskars Corporation introduced new methods to scissors manufacturing.
A pair of scissors consists of two pivoted blades. In lower-quality scissors the cutting edges are not particularly sharp; it is primarily the shearing action between the two blades that cuts the material. In high-quality scissors the blades can be both extremely sharp, and tension sprung - to increase the cutting and shearing tension only at the exact point where the blades meet. The hand movement (pushing with the thumb, pulling with the fingers in right handed use) can add to this tension. An ideal example is in high-quality tailor's scissors or shears, which need to be able to perfectly cut (and not simply tear apart) delicate cloths such as chiffon and silk.
Children's scissors are usually not particularly sharp, and the tips of the blades are often blunted or 'rounded' for safety.
Mechanically, scissors are a first-class double-lever with the pivot acting as the fulcrum. For cutting thick or heavy material, the mechanical advantage of a lever can be exploited by placing the material to be cut as close to the fulcrum as possible. For example, if the applied force (at the handles) is twice as far away from the fulcrum as the cutting location (i.e., the point of contact between the blades), the force at the cutting location is twice that of the applied force at the handles. Scissors cut material by applying a local shear stress at the cutting location which exceeds the material's shear strength.
Some scissors have an appendage, called a finger brace or finger tang, below the index finger hole for the middle finger to rest on to provide for better control and more power in precision cutting. A finger tang can be found on many quality scissors (including inexpensive ones) and especially on scissors for cutting hair (see hair scissors pictured below). In hair cutting, some claim the ring finger is inserted where some place their index finger, and the little finger rests on the finger tang.
For people who do not have the use of their hands, there are specially designed foot operated scissors. Some quadriplegics can use a motorized mouth-operated style of scissor.
Most scissors are best-suited for use with the right hand, but left-handed scissors are designed for use with the left hand. Because scissors have overlapping blades, they are not symmetric. This asymmetry is true regardless of the orientation and shape of the handles: the blade that is on top always forms the same diagonal regardless of orientation. Human hands are also asymmetric, and when closing, the thumb and fingers do not close vertically, but have a lateral component to the motion. Specifically, the thumb pushes out from the palm and the fingers pull inwards. For right-handed scissors held in the right hand, the thumb blade is closer to the user's body, so that the natural tendency of the right hand is to force the cutting blades together. Conversely, if right-handed scissors are held in the left hand, the natural tendency of the left hand would be to force the cutting blades laterally apart. Furthermore, with right-handed scissors held by the right-hand, the shearing edge is visible, but when used with the left hand, the cutting edge of the scissors is behind the top blade, and one cannot see what is being cut.
Some scissors are marketed as ambidextrous. These have symmetric handles so there is no distinction between the thumb and finger handles, and have very strong pivots so that the blades simply rotate and do not have any lateral give. However, most "ambidextrous" scissors are in fact still right-handed in that the upper blade is on the right, and hence is on the outside when held in the right hand. Even if they successfully cut, the blade orientation will block the view of the cutting line for a left-handed person. True ambidextrous scissors are possible if the blades are double-edged and one handle is swung all the way around (to almost 360 degrees) so that the back of the blades become the new cutting edges. Patents (U.S. Patent 3,978,584) have been awarded for true ambidextrous scissors.
Among specialized scissors and shears used for different purposes are:
Due to their ubiquity across cultures and classes, scissors have numerous representations across world culture.
Numerous forms of art worldwide enlist scissors as a tool/material with which to accomplish the art; in this section, we will be looking at cases where scissors appear in or are represented by the final art product.
The game Rock-Paper-Scissors involves two or more players making shapes with their hands to determine the outcome of the game. One of the three shapes, 'scissors', is made by extending the index and middle fingers to mimic the shape of most scissors.
The term 'scissor kick' may be found in several sports, including:
Scissors have a widespread place in cultural superstitions. In many cases, the specifics of the superstition may be specific to a given country, region, tribe, religion or even situation.
Scissors have been used in the sciences for various purposes, including descriptions of animals or natural features.
Animals named after scissors include:
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