A funnel is a tube or pipe that is wide at the top and narrow at the bottom, used for guiding liquid or powder into a small opening. Funnels are usually made of stainless steel,

aluminium Aluminium (aluminum in AmE, American and CanE, Canadian English) is a chemical element with the Symbol (chemistry), symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately o ...

glass Glass is a non-Crystallinity, crystalline, often transparency and translucency, transparent, amorphous solid that has widespread practical, technological, and decorative use in, for example, window panes, tableware, and optics. Glass is most ...

, or

plastic Plastics are a wide range of synthetic or semi-synthetic materials that use polymers as a main ingredient. Their plasticity makes it possible for plastics to be moulded, extruded or pressed into solid objects of various shapes. This adaptab ...

. The material used in its construction should be sturdy enough to withstand the weight of the substance being transferred, and it should not react with the substance. For this reason, stainless steel or glass are useful in transferring diesel, while plastic funnels are useful in the kitchen. Sometimes disposable

paper Paper is a thin sheet material produced by mechanically or chemically processing cellulose fibres derived from wood, Textile, rags, poaceae, grasses or other vegetable sources in water, draining the water through fine mesh leaving the fibre e ...

funnels are used in cases where it would be difficult to adequately clean the funnel afterwards (for example, in adding

motor oil Motor oil, engine oil, or engine lubricant is any one of various substances used for the lubrication of internal combustion engines. They typically consist of base oils enhanced with various additives, particularly antiwear additives, deterg ...

into a car). Dropper funnels, also called

dropping funnels Drop, DROP, drops or DROPS may refer to: * Drop (liquid) or droplet, a small volume of liquid ** Eye drops, saline (sometimes mydriatic) drops used as medication for the eyes * Drop (unit), a unit of measure of volume * Falling (physics), allowin ...

or tap funnels, have a tap to allow the controlled release of a liquid. A flat funnel, made of polypropylene, utilises

living hinge A living hinge or integral hinge is a thin flexible hinge ( flexure bearing) made from the same material as the two rigid pieces it connects. It is typically thinned or cut to allow the rigid pieces to bend along the line of the hinge. The m ...

s and flexible walls to fold flat. The term "funnel" may refer to the chimney or smokestack on a steam locomotive and commonly refers to the same on a ship. The term ''funnel'' is also applied to other seemingly strange objects like a smoking pipe or a kitchen bin.

Laboratory funnels

There are many different kinds of funnels that have been adapted for specialised applications in the laboratory.

Filter funnel A filter funnel is a laboratory funnel used for separating solids from liquids via the laboratory process of filtering. In order to achieve this, a cone-like shaped piece of filter paper is usually folded into a cone and placed within the funnel. ...

thistle funnel A thistle tube is a piece of laboratory glassware consisting of a shaft of tube, with a reservoir and funnel-like section at the top. Thistle tubes are typically used by chemists to add liquid to an existing system or apparatus. Thistle funnels a ...

s (shaped like

thistle Thistle is the common name of a group of flowering plants characterised by leaves with sharp prickles on the margins, mostly in the family Asteraceae. Prickles can also occur all over the planton the stem and on the flat parts of the leaves ...

flowers), and dropping funnels have stopcocks which allow the fluids to be added to a flask slowly. For solids, a powder funnel with a wide and short stem is more appropriate as it does not clog easily. When used with

filter paper Filter paper is a semi-permeable paper barrier placed perpendicular to a liquid or air flow. It is used to separate fine solid particles from liquids or gases. The raw materials are different Pulp (paper), paper pulps. The pulp may be made from soft ...

, filter funnels, Büchner and

Hirsch funnel Hirsch may refer to: Places * Hirsch, Saskatchewan, Canada * Hirsch Observatory, in Troy, New York, U.S. People * Afua Hirsch (born 1981), Norwegian-born British writer, broadcaster, and former barrister * Alex Hirsch (born 1985), American anim ...

s can be used to remove fine particles from a liquid in a process called

filtration Filtration is a physical separation process that separates solid matter and fluid from a mixture using a ''filter medium'' that has a complex structure through which only the fluid can pass. Solid particles that cannot pass through the filte ...

. For more demanding applications, the filter paper in the latter two may be replaced with a sintered glass frit. Separatory funnels are used in liquid-liquid extractions. The

Tullgren funnel A Berlese funnel, also known as Tullgren funnel, Berlese trap, or Berlese-Tullgren funnel, is an apparatus used to extract living organisms, particularly arthropods, from samples of soil. The Tullgren funnel works by creating a desiccation gradien ...

is used to collect

arthropod Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a Segmentation (biology), segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and Arth ...

s from

plant litter Plant litter (also leaf litter, tree litter, soil litter, litterfall or duff) is dead plant material (such as leaves, bark, needles, twigs, and cladodes) that have fallen to the ground. This detritus or dead organic material and its constitue ...

or similar material.

Construction

Glass is the material of choice for laboratory applications due to its inertness compared with metals or plastics. However, plastic funnels made of nonreactive

polyethylene Polyethylene or polythene (abbreviated PE; IUPAC name polyethene or poly(methylene)) is the most commonly produced plastic. It is a polymer, primarily used for packaging (plastic bags, plastic films, geomembranes and containers including ...

are used for transferring aqueous solutions. Plastic is most often used for powder funnels that do not come into contact with solvent in normal use.

Uses

* To channel

liquids A liquid is a nearly incompressible fluid that conforms to the shape of its container but retains a (nearly) constant volume independent of pressure. As such, it is one of the four fundamental states of matter (the others being solid, gas, ...

or fine-grained substances into containers with a small opening. Used for pouring liquids or powder through a small opening and for holding the filter paper in filtration. Used in transferring liquids in small containers. * Funnels known as

killing cone A killing cone, also known as a restraining cone or poultry cone, is a funnel used in the slaughter of poultry. The cone is used to hold a to-be slaughtered bird upside down, thus allowing for the animal to be bled more easily. Description Kil ...

s are used to slaughter individual birds in

poultry farming Poultry farming is the form of animal husbandry which raises domesticated birds such as chickens, ducks, turkeys and geese to produce meat or eggs for food. Poultry – mostly chickens – are farmed in great numbers. More than 60 billion ch ...

. The funnel is used to hold a bird upside down so that it can be bled more easily.SPARREY, J., SANDERCOCK, D., SPARKS, N., & SANDILANDS, V. (2014). Current and novel methods for killing poultry individually on-farm. ''World's Poultry Science Journal,'' ''70''(4), 737-758. doi:10.1017/S0043933914000816

Culture

Hieronymus Bosch-Removing the Rocks from the Head-Detail

The inverted funnel is a symbol of madness. It appears in many Medieval depictions of the mad; for example, in

Hieronymus Bosch Hieronymus Bosch (, ; born Jheronimus van Aken ; – 9 August 1516) was a Dutch/ Netherlandish painter from Brabant. He is one of the most notable representatives of the Early Netherlandish painting school. His work, generally oil on o ...

's '' Ship of Fools'' and '' Allegory of Gluttony and Lust''. In popular culture, the

Tin Woodman Nick Chopper, the Tin Woodman, also known as the Tin Man or—mistakenly—the "Tin Woodsman," is a character in the fictional Land of Oz created by American author L. Frank Baum. Baum's Tin Woodman first appeared in his classic 1900 book '' ...

in L. Frank Baum's novel ''

The Wonderful Wizard of Oz ''The Wonderful Wizard of Oz'' is a children's novel written by author L. Frank Baum and illustrated by W. W. Denslow. It is the first novel in the Oz series of books. A Kansas farm girl named Dorothy ends up in the magical Land of Oz aft ...

'' (and in most dramatizations of it) uses an inverted funnel for a hat, though that is never specifically mentioned in the story—it originated in W. W. Denslow's original illustrations for the book. In the East Coast of the United States, "beer funnel" is another term for "beer bong". "Funneling" a beer involves pouring an entire beer into a funnel attached to a tube, in which a person then consumes the beer via the tube. In the computing world, a funnel is frequently used as the icon for the filter functionality.

References

External links