Net (device)

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A cargo net being used to unload sacks from a ship at Haikou New Port, Haikou City, Hainan, China Cargo net 01.jpg
A cargo net being used to unload sacks from a ship at Haikou New Port, Haikou City, Hainan, China

A net comprises threads or yarns knotted and twisted into a grid-like structure which blocks the passage of large items, while letting small items and fluids pass. It requires less material than something sheet-like, and provides a degree of transparency, as well as flexibility and lightness.

Contents

Nets have been constructed by human beings since at least the Mesolithic period for use in capturing or retaining things. Their open structure provide lightness and flexibility that allow them to be carried and manipulated with relative ease, making them valuable for methodical tasks such as hunting, fishing, sleeping, and carrying.

History

A fragment of neolithic fishing net. HMB Fischernetz Jungsteinzeit.jpg
A fragment of neolithic fishing net.

The oldest nets found are from the Mesolithic era, but nets may have existed in the Upper Paleolithic era. [1] Nets are typically made of perishable materials and leave little archeological record. Some nets are preserved in ice or bogs, and there are also clay impressions of nets.

Making and repairing nets

One method of making nets is by tying sheet bends using a netting needle and a gauge. Key: *a) head rope *f) loop of the sheet bend being tied *n) netting shuttle *s) gauge *z) tongue of the netting shuttle (makes it easier to load the twine so that it does not twist as it is used) Netmaking.png
One method of making nets is by tying sheet bends using a netting needle and a gauge. Key: *a) head rope *f) loop of the sheet bend being tied *n) netting shuttle *s) gauge *z) tongue of the netting shuttle (makes it easier to load the twine so that it does not twist as it is used)
Mending a net; binding a length of net to a new head rope. Note that, unusually, the gauge of the row being worked is larger than the gauge of the rest of the net. A Fisherman mending his Net.jpg
Mending a net; binding a length of net to a new head rope. Note that, unusually, the gauge of the row being worked is larger than the gauge of the rest of the net.
Some nets are still made by hand. This 2013 image shows a Syrian refugee in Lebanon in her home, manually knotting a fishing net intended for sale. "The training is good, it's great. It helps us to learn and to earn a living" (11173845336).jpg
Some nets are still made by hand. This 2013 image shows a Syrian refugee in Lebanon in her home, manually knotting a fishing net intended for sale.

Originally, all nets were made by hand. Construction begins from a single point for round nets such as purse nets, net bags, or hair nets, but square nets are usually started from a headrope. [3] A line is tied to the headrope at regular intervals, forming a series of loops. This can be done using slipped overhand knots or other knots, such as clove hitches. Subsequent rows are then worked using sheet bends, as shown in the diagram, or another knot. Some nets, such as hammocks, may be looped rather than knotted.

To avoid hauling a long length of loose twine through each knot, the twine is wound onto a netting shuttle or netting needle. This must be done correctly to prevent it twisting as it is used, [3] but makes net production much faster. A gauge – often a smooth stick – is used to keep the loops the same size and the mesh even. The first and last rows are generally made using a half-size gauge, so that the edges of the net will be smooth. There are also knot-free nets.

Some nets are still shaped by their end users, [4] although nets are now often knotted by machine.

When a hole is ripped in a net, there are fewer holes in it than before the net was ripped. However, the stress concentration at the edges of the hole often causes it to tear further, making timely repairs important. Mending nets by hand is still an important skill for those who work with them.

Materials

Nets may be made using almost any sort of fiber. Traditional net materials varied with what was locally available; early European fishing nets were often made of linen, for instance. Longer-lasting synthetics are now fairly universal. Nylon monofilament nets are transparent, and are therefore often used for fishing and trapping.

Structural properties

Finishing a Mayan hammock, which is twisted rather than knotted. Copia (2) de DSC08077.JPG
Finishing a Mayan hammock, which is twisted rather than knotted.
The twisted net of a Mayan hammock is very stretchy, letting it hold this sleeping baby securely. Baby in mexikanischer Hangematte A la Siesta 2011.jpg
The twisted net of a Mayan hammock is very stretchy, letting it hold this sleeping baby securely.

Nets, like fabric, stretch less along their constituent strands (the "bars" between knots) than diagonally across the gaps in the mesh. They are, so to speak, made on the bias. The choice of material used also affects the structural properties of the net. Nets are designed and constructed for their specific purpose by modifying the parameters of the weave and the material used. Safety nets, for example, must decelerate the person hitting them gradually, usually by having a concave-upwards stress–strain curve, where the amount of force required to stretch the net increases the further the net is stretched.

Uses

Transport

Examples include cargo nets and net bags. Some vegetables, like onions, are often shipped in nets.

Sports

Nets are used in sporting goals and in games such as soccer, basketball, bossaball and ice hockey. A net separates opponents in various net sports such as volleyball, tennis, badminton, and table tennis, where the ball or shuttlecock must go over the net to remain in play. A net also may be used for safety during practice, as in cricket.

Capturing animals

Nets for capturing animals include fishing nets, butterfly nets, bird netting, and trapping nets such as purse and long nets. Some, like mist nets, rocket nets, and netguns, are designed not to harm the animals caught. Camouflage nets may also be used.

Furnishings

Hammocks, safety nets, and mosquito nets are net-based. Some furniture includes a net stretched on a frame. Multihull boats may have net trampolines strung between their hulls.

Clothing

Hair nets, net lace, and net embroidery are sartorial nets.

Armed conflict

Anti-submarine nets and anti-torpedo nets can be laid by net-laying ships.

See also

Related Research Articles

<span class="mw-page-title-main">Hammock</span> Sling used for swinging, sleeping or resting

A hammock, from Spanish hamaca, borrowed from Taíno and Arawak hamaka, is a sling made of fabric, rope, or netting, suspended between two or more points, used for swinging, sleeping, or resting. It normally consists of one or more cloth panels, or a woven network of twine or thin rope stretched with ropes between two firm anchor points such as trees or posts. Hammocks were developed by native inhabitants of the Americas for sleeping, as well as the English. Later, they were used aboard ships by sailors to enable comfort and maximize available space, by explorers or soldiers travelling in wooded regions and eventually by parents in the early 1920s for containing babies just learning to crawl. Today they are popular around the world for relaxation; they are also used as a lightweight bed on camping trips. The hammock is often seen as a symbol of summer, leisure, relaxation and simple, easy living.

<span class="mw-page-title-main">Webbing</span> Strong fabric woven as a flat strip or tube used instead of rope

Webbing is a strong fabric woven as a flat strip or tube of varying width and fibres, often used in place of rope. It is a versatile component used in climbing, slacklining, furniture manufacturing, automobile safety, auto racing, towing, parachuting, military apparel, load securing, and many other fields.

<span class="mw-page-title-main">Gillnetting</span> Type of fishing net

Gillnetting is a fishing method that uses gillnets: vertical panels of netting that hang from a line with regularly spaced floaters that hold the line on the surface of the water. The floats are sometimes called "corks" and the line with corks is generally referred to as a "cork line." The line along the bottom of the panels is generally weighted. Traditionally this line has been weighted with lead and may be referred to as "lead line." A gillnet is normally set in a straight line. Gillnets can be characterized by mesh size, as well as colour and type of filament from which they are made. Fish may be caught by gillnets in three ways:

  1. Wedged – held by the mesh around the body.
  2. Gilled – held by mesh slipping behind the opercula.
  3. Tangled – held by teeth, spines, maxillaries, or other protrusions without the body penetrating the mesh.
<span class="mw-page-title-main">Fishing net</span> Net used for fishing

A fishing net is a net used for fishing. Some fishing nets are also called fish traps, for example fyke nets. Fishing nets are usually meshes formed by knotting a relatively thin thread. Early nets were woven from grasses, flaxes and other fibrous plant material. Later cotton was used. Modern nets are usually made of artificial polyamides like nylon, although nets of organic polyamides such as wool or silk thread were common until recently and are still used.

<span class="mw-page-title-main">Mist net</span> Net used to capture wild birds or bats

Mist nets are used by hunters and poachers, but also by ornithologists and chiropterologists to capture wild birds and bats for banding or other research projects. Mist nets are typically made of nylon or polyester mesh suspended between two poles, resembling a volleyball net. When properly deployed in the correct habitat, the nets are virtually invisible. Mist nets have shelves created by horizontally strung lines that create a loose, baggy pocket. When a bird or bat hits the net, it falls into this pocket, where it becomes tangled.

<span class="mw-page-title-main">Lobster trap</span> Portable trap used in lobster fishing

A lobster trap or lobster pot is a portable trap that traps lobsters or crayfish and is used in lobster fishing. In Scotland, the word creel is used to refer to a device used to catch lobsters and other crustaceans. A lobster trap can hold several lobsters. Lobster traps can be constructed of wire and wood, metal and netting, or rigid plastic. An opening permits the lobster to enter a tunnel of netting or other one-way device. Pots are sometimes constructed in two parts, called the "chamber" or "kitchen", where there is bait, and exits into the "parlor", which prevents escape. Lobster pots are usually dropped to the sea floor, one or more at a time, sometimes up to 40 or more, and are marked by a buoy so they can be picked up later.

<span class="mw-page-title-main">Seine fishing</span> Method of fishing with a net

Seine fishing is a method of fishing that employs a surrounding net, called a seine, that hangs vertically in the water with its bottom edge held down by weights and its top edge buoyed by floats. Seine nets can be deployed from the shore as a beach seine, or from a boat.

Filet lace is the general word used for all the different techniques of embroidery on knotted net. It is a hand made needlework created by weaving or embroidery using a long blunt needle and a thread on a ground of knotted net lace or filet work made of square or diagonal meshes of the same sizes or of different sizes. Lacis uses the same technique but is made on a ground of leno or small canvas.

<span class="mw-page-title-main">Cricket nets</span>

Cricket nets are used by batters and bowlers to practice their cricketing techniques. They consist of a cricket pitch enclosed by netting on either side, behind, and optionally above. The bowling end is left open.

<span class="mw-page-title-main">Drift netting</span> Fishing technique

Drift netting is a fishing technique where nets, called drift nets, hang vertically in the water column without being anchored to the bottom. The nets are kept vertical in the water by floats attached to a rope along the top of the net and weights attached to another rope along the bottom of the net. Drift nets generally rely on the entanglement properties of loosely affixed netting. Folds of loose netting, much like a window drapery, snag on a fish's tail and fins and wrap the fish up in loose netting as it struggles to escape. However, the nets can also function as gill nets if fish are captured when their gills get stuck in the net. The size of the mesh varies depending on the fish being targeted. These nets usually target schools of pelagic fish.

<span class="mw-page-title-main">Fishing tackle</span> Equipment used for fishing

Fishing tackle is the equipment used by anglers when fishing. Almost any equipment or gear used in fishing can be called fishing tackle, examples being hooks, lines, baits/lures, rods, reels, floats, sinkers/feeders, nets, spears, gaffs and traps, as well as wires, snaps, beads, spoons, blades, spinners, clevises and tools that make it easy to tie knots.

<span class="mw-page-title-main">Hammock camping</span>

Hammock camping is a form of camping in which a camper sleeps in a suspended hammock rather than a conventional tent on the ground. Due to the absence of poles and the reduced amount of material used, hammocks can be lighter than a tent, though this is not always the case. Most hammocks will also require less space in a pack than a similar occupancy tent. In foul weather, a tarp is suspended above the hammock to keep the rain off of the camper. Mosquito netting, sometimes integrated into the camping hammock itself, is also used as climatic conditions warrant. Camping hammocks are used by campers who are looking for lighter weight, protection from ground-dwelling insects, or other ground complications such as sloped ground, rocky terrain and flooded terrain.

<span class="mw-page-title-main">Safety net</span> Type of net

A safety net is a net to protect people from injury after falling from heights by limiting the distance they fall, and deflecting to dissipate the impact energy. The term also refers to devices for arresting falling or flying objects for the safety of people beyond or below the net. Safety nets are used in construction, building maintenance, entertainment, or other industries.

The manufacture of textiles is one of the oldest of human technologies. To make textiles, the first requirement is a source of fiber from which a yarn can be made, primarily by spinning. The yarn is processed by knitting or weaving, which turns yarn into cloth. The machine used for weaving is the loom. For decoration, the process of colouring yarn or the finished material is dyeing. For more information of the various steps, see textile manufacturing.

<span class="mw-page-title-main">Net (textile)</span>

Net or netting is any textile in which the yarns are fused, looped or knotted at their intersections, resulting in a fabric with open spaces between the yarns. Net has many uses, and comes in different varieties. Depending on the type of yarn or filament that is used to make up the textile, its characteristics can vary from durable to not durable.

<span class="mw-page-title-main">Fishing techniques</span> Methods for catching sea creatures, especially fish

Fishing techniques are methods for catching fish. The term may also be applied to methods for catching other aquatic animals such as molluscs and edible marine invertebrates.

<span class="mw-page-title-main">Cast net</span>

A casting net, also called a throw net, is a net used for fishing. It is a circular net with small weights distributed around its edge.

<span class="mw-page-title-main">Hand net</span> Type of fishing net

A hand net, also called a scoop net, is a handheld fishing net or meshed basket used to capture and retrieve objects from water, somewhat in the manner of a sieve. It is distinguished from other fishing nets in that the net or mesh is supported by a rigid circular or polygonal frame, which may or may not be mounted to the end of a handle.

<span class="mw-page-title-main">String bag</span> Open netted bag

A string bag, net bag, or mesh bag is an open netted bag. Mesh bags are constructed from strands, yarns, or non-woven synthetic material into a net-like structure. String bags are used as reusable shopping bags and as packaging for produce.

<span class="mw-page-title-main">String (structure)</span> Flexible structure made from fibers twisted together

String is a long flexible structure made from fibers twisted together into a single strand, or from multiple such strands which are in turn twisted together. String is used to tie, bind, or hang other objects. It is also used as a material to make things, such as textiles, and in arts and crafts. String is a simple tool, and its use by humans is known to have been developed tens of thousands of years ago. In Mesoamerica, for example, string was invented some 20,000 to 30,000 years ago, and was made by twisting plant fibers together. String may also be a component in other tools, and in devices as diverse as weapons, musical instruments, and toys.

References

  1. Martin Trachsel (2008), Ur- und Frühgeschichte: Quellen, Methoden, Ziele (in German), UTB, p. 56, ISBN   3-8252-8369-0
  2. "Fishing nets for a future: helping Syrian women in Lebanon". webarchive.nationalarchives.gov.uk. Archived from the original on 2013-06-03. Retrieved 2015-04-08.
  3. 1 2 Netting instructions
  4. Net making (and repair) guide for commercial fishing nets.