history of scissors

Scissors are hand-operated cutting 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 and food. Scissors and shears are functionally equivalent, but larger implements tend to be called shears.
There are many types of scissors and shears for different purposes. For example, children's scissors, used only on paper, have dull blades and rounded corners to ensure safety. Scissors used to cut hair or fabric must be much sharper. The largest shears used to cut metal or to trim shrubs must have very strong, sharp blades.
Specialized scissors include sewing scissors, which often have one sharp point and one blunt point for intricate cutting of fabric, and nail scissors, which sometimes have curved blades for cutting fingernails and toenails.
Special kinds of shears include pinking shears, which have notched blades that cut cloth to give it a wavy edge, and thinning shears, which have teeth that cut every second hair strand, rather than every strand giving the illusion of thinner hair.
The noun "scissors" is treated as a plural noun, and therefore takes a plural verb ("these scissors are"). Alternatively, this tool is also referred to as "a pair of scissors", in which case it (a pair) is singular and therefore takes a singular verb ("this pair of scissors is").
The word shears is used to describe similar instruments that are larger in size and for heavier cutting. Geographical opinions vary as to the size at which 'scissors' become 'shears', but this is often at between six to eight inches 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 sixteenth 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 AD 100. 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. is officially recognized as first starting the manufacture of scissors in the year 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 nineteenth 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 a part of Sweden that is now in Finland, an ironworks was founded in the "Fiskars" hamlet 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 tailors scissors or shears, which need to be able 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 (i.e., the hand) is twice as far away from the fulcrum as the cutting location (e.g., piece of paper), 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.
Specialized scissors, such as bolt cutters, exploit leverage by having a long handle but placing the material to be cut close to the fulcrum.
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.
Kitchen scissors, also known as kitchen shears, are traditionally used in the kitchen for food preparation, although due to their tough nature they can serve many other purposes. In modern times they are often made from stainless steel (for food hygiene and oxidization-resistance reasons). They often have kitchen functionality (other than cutting) incorporated, such as bottle-cap and bottle-openers built into the handles.
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 and fingers pull inwards. For right-handed scissors held in the right hand, the thumb blade is further from 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 have been awarded for true ambidextrous scissors.