The reef knot, or square knot, is an ancient and simple
binding knot
Binding may refer to:
Computing
* Binding, associating a network socket with a local port number and IP address
* Data binding, the technique of connecting two data elements together
** UI data binding, linking a user interface element to an elem ...
used to secure a rope or line around an object. It is sometimes also referred to as a Hercules knot. The
knot
A knot is an intentional complication in cordage which may be practical or decorative, or both. Practical knots are classified by function, including hitches, bends, loop knots, and splices: a ''hitch'' fastens a rope to another object; a ' ...
is formed by tying a left-handed
overhand knot
The overhand knot is one of the most fundamental knots, and it forms the basis of many others, including the simple noose, overhand loop, angler's loop, reef knot, fisherman's knot, Half hitch, and water knot. The overhand knot is a stopper, ...
between two ends, instead of around one end, and then a right-handed overhand knot via the same procedure, or vice versa. A common
mnemonic
A mnemonic ( ) device, or memory device, is any learning technique that aids information retention or retrieval (remembering) in the human memory for better understanding.
Mnemonics make use of elaborative encoding, retrieval cues, and imag ...
for this procedure is "right over left; left over right", which is often appended with the rhyming suffix "... makes a knot both tidy and tight". Two consecutive overhands tied as described above of the same
handedness will make a
granny knot
The granny knot is a binding knot, used to secure a rope or line around an object. It is considered inferior to the reef knot (square knot), which it superficially resembles. Neither of these knots should be used as a bend knot for attaching tw ...
. The
working end
A knot is an intentional complication in cordage which may be practical or decorative, or both. Practical knots are classified by function, including hitches, bends, loop knots, and splices: a ''hitch'' fastens a rope to another object; a ' ...
s of the reef knot must emerge both at the top or both at the bottom, otherwise a
thief knot
The thief's knot resembles the reef knot (square knot) except that the free, or bitter ends are on opposite sides. It is said that sailors would secure their belongings in a ditty bag using the thief knot, often with the ends hidden. If anoth ...
results.
The reef knot is not recommended for
tying two ropes together, because of the potential instability of the knot when not stabilized; something that has resulted in many deaths (see
Misuse as a bend).
Naming
The reef knot is at least 4,000 years old. The name "reef knot" dates from at least 1794
and originates from its common use to
reef
A reef is a ridge or shoal of rock, coral or similar relatively stable material, lying beneath the surface of a natural body of water. Many reefs result from natural, abiotic processes— deposition of sand, wave erosion planing down rock o ...
sails,
that is to tie part of the
sail down to decrease its effective surface area in strong
wind
Wind is the natural movement of air or other gases relative to a planet's surface. Winds occur on a range of scales, from thunderstorm flows lasting tens of minutes, to local breezes generated by heating of land surfaces and lasting a few ho ...
s. To release the knot a
sailor
A sailor, seaman, mariner, or seafarer is a person who works aboard a watercraft as part of its crew, and may work in any one of a number of different fields that are related to the operation and maintenance of a ship.
The profession of the s ...
could collapse it with a pull of one hand; the sail's weight would make the collapsed knot come apart. It is specifically this behavior which makes the knot unsafe for connecting two ropes together.
The name "square knot" is found in
Dana's 1841 maritime compendium ''A Seaman's Friend'', which also gives "reef knot" as an alternative name.
[Ashley, p. 220.]
The name ''square knot'' is often used for the unslipped version of reef knot. ''Reef knot'' itself then is understood as the single slipped version, while the name
shoelace knot is to indicate double slipped version. Sometimes the name bowtie also may be used to indicate a double slipped version, but tying a bowtie is usually performed on flat material, and involves a
slip knot
The slip knot is a stopper knot which is easily undone by pulling the tail ( working end). The slip knot is related to the running knot, which will release when the standing end is pulled. Both knots are identical and are composed of a slippe ...
of one end holding a bight of the other end i.e. not really a double slipped reef knot. The name "Square knot" is also used for completely different other knots such as the mathematical concept of
square knot, or
friendship knot
The friendship knot is a decorative knot which is used to tie neckerchieves, lanyards and in Chinese knotting.
History and use
This is one of the eleven basic knots of traditional Chinese knotting, a craft which began in the Tang and Song Dyn ...
; this last one earns the name by being flat and drawing a square on one face (and a cross on the other face).
Uses
The reef knot is used to tie the two ends of a single rope together such that they will secure something, for example a bundle of objects, that is unlikely to move much. In addition to being used by sailors for
reefing
Reefing reduces the area of a sail, usually by folding or rolling one edge of the canvas in on itself and attaching the unused portion to a spar or a stay, as the primary measure to preserve a sailing vessel's stability in strong winds. Restoring ...
and
furling sails, it is also one of the key knots of
macrame textiles.
[Ashley, pp. 399-400.]
The knot lies flat when made with cloth and has been used for tying
bandage
A bandage is a piece of material used either to support a medical device such as a dressing or splint, or on its own to provide support to or to restrict the movement of a part of the body. When used with a dressing, the dressing is applie ...
s for millennia. As a binding knot it was known to the
ancient Greeks
Ancient Greece ( el, Ἑλλάς, Hellás) was a northeastern Mediterranean civilization, existing from the Greek Dark Ages of the 12th–9th centuries BC to the end of classical antiquity ( AD 600), that comprised a loose collection of cult ...
as the
Hercules
Hercules (, ) is the Roman equivalent of the Greek divine hero Heracles, son of Jupiter and the mortal Alcmena. In classical mythology, Hercules is famous for his strength and for his numerous far-ranging adventures.
The Romans adapted the ...
knot (''Herakleotikon hamma'') and is still used extensively in medicine.
In his ''
Natural History'',
Pliny
Pliny may refer to:
People
* Pliny the Elder (23–79 CE), ancient Roman nobleman, scientist, historian, and author of ''Naturalis Historia'' (''Pliny's Natural History'')
* Pliny the Younger (died 113), ancient Roman statesman, orator, w ...
relates the belief that
wounds heal more quickly when bound with a Hercules knot.
It has also been used since ancient times to tie
belt
Belt may refer to:
Apparel
* Belt (clothing), a leather or fabric band worn around the waist
* Championship belt, a type of trophy used primarily in combat sports
* Colored belts, such as a black belt or red belt, worn by martial arts practit ...
s and
sash
A sash is a large and usually colorful ribbon or band of material worn around the body, either draping from one shoulder to the opposing hip and back up, or else running around the waist. The sash around the waist may be worn in daily attire, bu ...
es. A modern use in this manner includes tying the
obi #REDIRECT Obi {{redirect category shell, {{R from other capitalisation{{R from ambiguous title ...
(or belt) of a
martial arts keikogi
(, "practice", , "dress or "clothes"), also known as or , is a traditional uniform worn for training in Japanese martial arts and their derivatives. Emerging in the late 19th century, the was developed by judo founder Kanō Jigorō.
Origin
Ja ...
.
With both ends tucked (slipped) it becomes a good way to tie
shoelaces
Shoelaces, also called shoestrings (US English) or bootlaces (UK English), are a system commonly used to secure shoes, boots, and other footwear. They typically consist of a pair of strings or cords, one for each shoe, finished off at both end ...
, whilst the non-slipped version is useful for shoelaces that are excessively short. It is appropriate for tying plastic garbage or trash bags, as the knot forms a handle when tied in two twisted edges of the bag.
The reef knot figures prominently in
Scouting worldwide. It is included in the international membership badge
[See :File:World Scout Emblem 1955.svg for an image of the emblem.] and many
scouting awards.
In the Boy Scouts of America demonstrating the proper tying of the square knot is a requirement for all boys joining the program.
In
Pioneering (Scouting), it is commonly used as a
binding knot
Binding may refer to:
Computing
* Binding, associating a network socket with a local port number and IP address
* Data binding, the technique of connecting two data elements together
** UI data binding, linking a user interface element to an elem ...
to finish off specialized
lashing (ropework)
A lashing is an arrangement of rope, wire, or webbing with linking device used to secure and fasten two or more items together in a somewhat rigid manner. Lashings are most commonly applied to timber poles, and are commonly associated with cargo, ...
and
whipping knot
A whipping knot or whipping is a binding (knot), binding of twine or Whipcord#Cord, whipcord around the end of a rope to prevent its natural tendency to fray.
Some whippings are finished cleanly, as by drawing the bitter end of the cordage b ...
s.
However, it is an insecure knot, unstable when jiggled, and is not suitable for supporting weight.
A
surgeon's variation, used where a third hand is unavailable, is made with two or three twists of the ropes on bottom, and sometimes on top, instead of just one.
File:Egypte louvre 279 couple detail reef knot.jpg, Detail of Egyptian
Egyptian describes something of, from, or related to Egypt.
Egyptian or Egyptians may refer to:
Nations and ethnic groups
* Egyptians, a national group in North Africa
** Egyptian culture, a complex and stable culture with thousands of years of ...
statue dating from 2350 BC depicting a reef knot securing a belt
File:Ancient Greek jewelry Pontika (Ukraina) 300 bC.jpg, Ancient Greek jewelry from Pontika (Ukraine), 300 BC, in the form of a reef knot
File:Kreuzknoten-slip.jpg, Singly slipped reef knot
File:Shoelace_knot.svg, Diagram of common shoelace bow knot, a doubly slipped reef knot
File:Akan MHNT.ETH.2010.25.060.jpg , Weight for weighing gold dust - Knot – MHNT
Misuse as a bend
The reef knot's familiarity, ease of tying, and visually appealing symmetry conceal its weakness. The
International Guild of Knot Tyers
The International Guild of Knot Tyers (or IGKT) is a worldwide association for people with an interest in knots and knot tying.
Formation and beginning
Officially established in 1982, the founding members were initially drawn together by the ...
warns that this knot should never be used to
bend two ropes together.
However, modern instruction teaches that it is fine for noncritical applications, especially if stabilized. A proper bend knot, for instance a
sheet bend
The sheet bend (also known as becket bend, weaver's knot and weaver's hitch) is a bend. It is practical for joining lines of different diameter or rigidity.
It is quick and easy to tie, and is considered so essential it is the first knot given ...
or
double fisherman's knot
The double fisherman's knot or grapevine knot is a bend. This knot and the triple fisherman's knot are the variations used most often in climbing, arboriculture, and search and rescue. The knot is formed by tying a double overhand knot, in its ...
, should be used instead. Knotting authority
Clifford Ashley claimed that misused reef knots have caused more deaths and injuries than all other knots combined.
[Ashley, p. 18.] Further, it is easily confused with the
granny knot
The granny knot is a binding knot, used to secure a rope or line around an object. It is considered inferior to the reef knot (square knot), which it superficially resembles. Neither of these knots should be used as a bend knot for attaching tw ...
, which is a very poor knot.
Physical analysis
An approximate physical analysis predicts that a reef knot will hold if
, where μ is the relevant
coefficient of friction
Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other. There are several types of friction:
*Dry friction is a force that opposes the relative lateral motion of t ...
. This inequality holds if
. Experiments show that the critical value of μ is actually somewhat lower.
[Crowell, "The physics of knots," http://www.lightandmatter.com/article/knots.html]
Related knots
See also
*
Shoelace knot
*
Granny knot
The granny knot is a binding knot, used to secure a rope or line around an object. It is considered inferior to the reef knot (square knot), which it superficially resembles. Neither of these knots should be used as a bend knot for attaching tw ...
*
Thief knot
The thief's knot resembles the reef knot (square knot) except that the free, or bitter ends are on opposite sides. It is said that sailors would secure their belongings in a ditty bag using the thief knot, often with the ends hidden. If anoth ...
*
Surgeon's knot
The surgeon's knot is a surgical knot and is a simple modification to the reef knot. It adds an extra twist when tying the first throw, forming a double overhand knot. The additional turn provides more friction and can reduce loosening while t ...
*
List of binding knots
*
List of knots
This list of knots includes many alternative names for common knots and lashings. Knot names have evolved over time, and there are many conflicting or confusing naming issues. The overhand knot, for example, is also known as the thumb knot. The ...
*
Square knot (emblem or insignia)
Square knot insignia are embroidered cloth patches that represent awards of the Scout associations throughout the world.
The Scout Association of the United Kingdom uses a "figure-eight" knot and many Scouting organizations of the Commonwealt ...
*
Reefing
Reefing reduces the area of a sail, usually by folding or rolling one edge of the canvas in on itself and attaching the unused portion to a spar or a stay, as the primary measure to preserve a sailing vessel's stability in strong winds. Restoring ...
Notes and references
External links
Knot of Hercules
{{DEFAULTSORT:Reef Knot
Scoutcraft