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51-420: This site is known primarily as a probable site of early horse domestication due to a high percentage of horse bones found at the site. A horse burial with bit wear and cheek pieces was long considered evidence for horseback-riding at an early date, but in 1997 radiocarbon dates showed that the burial was intrusive, the horse having died circa 700-200 BC, thereby re-opening the question of when horseback-riding

102-638: A ( F A ⋅ e A ⊥ ) − b ( F B ⋅ e B ⊥ ) = a F A − b F B , {\displaystyle F_{\theta }=\mathbf {F} _{A}\cdot {\frac {\partial \mathbf {v} _{A}}{\partial {\dot {\theta }}}}-\mathbf {F} _{B}\cdot {\frac {\partial \mathbf {v} _{B}}{\partial {\dot {\theta }}}}=a(\mathbf {F} _{A}\cdot \mathbf {e} _{A}^{\perp })-b(\mathbf {F} _{B}\cdot \mathbf {e} _{B}^{\perp })=aF_{A}-bF_{B},} where F A and F B are components of

153-504: A foot pedal was used for the earliest horizontal frame loom . In Mesopotamia (modern Iraq) c.  3000 BC , the shadouf , a crane-like device that uses a lever mechanism, was invented. In ancient Egypt , workmen used the lever to move and uplift obelisks weighing more than 100 tons. This is evident from the recesses in the large blocks and the handling bosses which could not be used for any purpose other than for levers. The earliest remaining writings regarding levers date from

204-431: A hinge, or pivot, called a fulcrum. The ideal lever does not dissipate or store energy, which means there is no friction in the hinge or bending in the beam. In this case, the power into the lever equals the power out, and the ratio of output to input force is given by the ratio of the distances from the fulcrum to the points of application of these forces. This is known as the law of the lever . The mechanical advantage of

255-446: A horse's bit is the first factor most people think of when assessing the severity and action of the bit. Therefore, it is carefully considered when choosing a bit for a horse. Many mouthpieces are not allowed in certain competitions. Bit mouthpieces may be single jointed, double-jointed, "mullen" (a straight bar), or have an arched port in the center of varying height, with or without joints. Some have rollers, rings or small "keys" that

306-446: A lever can be determined by considering the balance of moments or torque , T , about the fulcrum. If the distance traveled is greater, then the output force is lessened. T 1 = F 1 a , T 2 = F 2 b {\displaystyle {\begin{aligned}T_{1}&=F_{1}a,\quad \\T_{2}&=F_{2}b\!\end{aligned}}} where F 1

357-415: A lever is the ratio of output force to input force. M A = F 2 F 1 = a b . {\displaystyle MA={\frac {F_{2}}{F_{1}}}={\frac {a}{b}}.\!} This relationship shows that the mechanical advantage can be computed from ratio of the distances from the fulcrum to where the input and output forces are applied to the lever, assuming

408-403: A mouthpiece that is usually seen more often on curb bits, ridden with two reins; and the double bridle , which places a curb and a snaffle bit simultaneously in the horse's mouth so that each may act independently of the other, ridden with four reins. Another bit that combines direct pressure and leverage in a unique manner is the gag bit , a bit derived from the snaffle that, instead of having

459-438: A neutral effect on salivation; sweet iron , aurigan and copper , which generally tend to encourage salivation, and aluminum, which is considered drying and is discouraged as a mouthpiece metal. Synthetic mouthpieces may be made with or without internal metal cable or bar reinforcement. Rubber bits are generally thicker than metal bits, but other types of synthetics such as plastics are also used. Plastic-coated bits are often

510-435: A rein attached to the mouthpiece, runs the rein through a set of rings that attach directly to the headstall, creating extra pressure on the lips and poll when applied. Usually used for correction of specific problems, the gag bit is generally illegal in the show ring and racecourse. Bits and the behavior of horses while wearing bits have made their way into popular culture outside of the horse world. Lever A lever

561-423: A rigid bar connected to a ground frame by a hinged joint called a fulcrum. The lever is operated by applying an input force F A at a point A located by the coordinate vector r A on the bar. The lever then exerts an output force F B at the point B located by r B . The rotation of the lever about the fulcrum P is defined by the rotation angle θ in radians. Let the coordinate vector of

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612-399: A very high "spoon" or "spade" extension that contacts the roof of the mouth. The length of the shank determines the degree of leverage put on the horse's head and mouth. Again, a bit with shanks and leverage is always a "curb" type bit, even when it has a jointed mouthpiece more commonly seen on a snaffle (such bits are sometimes—incorrectly—called "cowboy snaffles"). All shanked bits require

663-415: A weightless lever and no losses due to friction, flexibility or wear. This remains true even though the "horizontal" distance (perpendicular to the pull of gravity) of both a and b change (diminish) as the lever changes to any position away from the horizontal. Levers are classified by the relative positions of the fulcrum, effort and resistance (or load). It is common to call the input force "effort" and

714-418: Is a simple machine consisting of a beam or rigid rod pivoted at a fixed hinge , or fulcrum . A lever is a rigid body capable of rotating on a point on itself. On the basis of the locations of fulcrum, load and effort, the lever is divided into three types . It is one of the six simple machines identified by Renaissance scientists. A lever amplifies an input force to provide a greater output force, which

765-640: Is evidence of the use of bits, located in two sites of the Botai culture in ancient Kazakhstan , dated about 3500–3000 BC. Nose rings appear on the equids portrayed on the Standard of Ur , circa 2600–2400 BC. To date, the earliest known artistic evidence of use of some form of bitless bridle comes in illustrations of Synian horseman, dated approximately 1400 BC. The first bits were made of rope, bone, horn, or hard wood. Metal bits came into use between 1300 and 1200 BC, originally made of bronze. In modern times, nickel

816-428: Is given by: M A = F B F A = a b . {\displaystyle MA={\frac {F_{B}}{F_{A}}}={\frac {a}{b}}.} This is the law of the lever , which was proven by Archimedes using geometric reasoning. It shows that if the distance a from the fulcrum to where the input force is applied (point A ) is greater than the distance b from fulcrum to where

867-450: Is said to provide leverage , which is mechanical advantage gained in the system, equal to the ratio of the output force to the input force. As such, the lever is a mechanical advantage device , trading off force against movement. The word "lever" entered English around AD 1300 from Old French : levier . This sprang from the stem of the verb lever , meaning "to raise". The verb, in turn, goes back to Latin : levare , itself from

918-481: Is the generalized coordinate that defines the configuration of the lever, and the generalized force associated with this coordinate is given by F θ = F A ⋅ ∂ v A ∂ θ ˙ − F B ⋅ ∂ v B ∂ θ ˙ =

969-445: Is the input force to the lever and F 2 is the output force. The distances a and b are the perpendicular distances between the forces and the fulcrum. Since the moments of torque must be balanced, T 1 = T 2 {\displaystyle T_{1}=T_{2}\!} . So, F 1 a = F 2 b {\displaystyle F_{1}a=F_{2}b\!} . The mechanical advantage of

1020-417: The bridle such as the curb chain on the chin, noseband on the jaw and face, or pressure on the poll from the headstall. Particular mouthpieces do not define the type of bit. It is the sidepieces and the leverage these rings or shanks use to act on a horse's mouth that determines whether a bit is in the curb or snaffle family, and has a great impact on the severity of the mouthpiece. The mouthpiece of

1071-422: The eardrum to the oval window of the cochlea . The lever is a movable bar that pivots on a fulcrum attached to a fixed point. The lever operates by applying forces at different distances from the fulcrum, or a pivot. As the lever rotates around the fulcrum, points further from this pivot move faster than points closer to the pivot. Therefore, a force applied to a point further from the pivot must be less than

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1122-438: The mullen , the piece that fits inside the horse's mouth. The mullen extends across the horse's mouth and rests on the bars , the region between the incisors and molars where there are no teeth . The bit is located on the horse's head by the headstall , and which has itself several components to allow the most comfortable adjustment of bit location and control. The bit, bridle and reins function together to give control of

1173-463: The 3rd century BC and were provided, by common belief, by the Greek mathematician Archimedes , who famously stated "Give me a lever long enough and a fulcrum on which to place it, and I shall move the world." Autumn Stanley argues that the digging stick can be considered the first lever, which would position prehistoric women as the inventors of lever technology. A lever is a beam connected to ground by

1224-451: The 3rd class lever. A compound lever comprises several levers acting in series: the resistance from one lever in a system of levers acts as effort for the next, and thus the applied force is transferred from one lever to the next. Examples of compound levers include scales, nail clippers and piano keys. The malleus , incus and stapes are small bones in the middle ear , connected as compound levers, that transfer sound waves from

1275-475: The 6500 BC to 4000 BC were also analyzed. Of the fourteen males analyzed, six carried I2a2 and various subclades of it, four carried I, one carried R1b1x M269, whilst the rest were lower coverage/ unresolved (R1*, I*, IJ*). In regard to mtDNA, all individuals except for a male who carried haplogroup T carried subclades of haplogroup U (U5, U4 and U2 ). Four Eneolithic individuals buried at Deriivka from ca. 4000 BC to 2700 BC were analyzed. With regard to Y-DNA,

1326-564: The adjective levis , meaning "light" (as in "not heavy"). The word's primary origin is the Proto-Indo-European stem legwh- , meaning "light", "easy" or "nimble", among other things. The PIE stem also gave rise to the English word "light". The earliest evidence of the lever mechanism dates back to the ancient Near East c.  5000 BC , when it was first used in a simple balance scale . In ancient Egypt c.  4400 BC ,

1377-437: The basic families of bits are defined by the way in which they use or do not use leverage . They include: Bits are further described by the style of mouthpiece that goes inside the horse's mouth as well as by the type of bit ring or bit shank that is outside the mouth, to which the reins are attached. Types of headgear for horses that exert control with a noseband rather than a bit are usually called hackamores , though

1428-421: The force located at a point closer in, because power is the product of force and velocity. If a and b are distances from the fulcrum to points A and B and the force F A applied to A is the input and the force F B applied at B is the output, the ratio of the velocities of points A and B is given by a/b , so we have the ratio of the output force to the input force, or mechanical advantage,

1479-400: The forces that are perpendicular to the radial segments PA and PB . The principle of virtual work states that at equilibrium the generalized force is zero, that is F θ = a F A − b F B = 0. {\displaystyle F_{\theta }=aF_{A}-bF_{B}=0.\,\!} Thus, the ratio of the output force F B to

1530-414: The front incisors and in front of the back molars . When a horse is said to "grab the bit in its teeth" they actually mean that the horse tenses its lips and mouth against the bit to avoid the rider's commands (although some horses may actually learn to get the bit between their molars). Depending on the style of bit, pressure can be brought to bear on the bars, tongue, and roof of the mouth, as well as

1581-542: The fulcrum to the input point A and to the output point B , respectively. Now introduce the unit vectors e A and e B from the fulcrum to the point A and B , so r A − r P = a e A , r B − r P = b e B . {\displaystyle \mathbf {r} _{A}-\mathbf {r} _{P}=a\mathbf {e} _{A},\quad \mathbf {r} _{B}-\mathbf {r} _{P}=b\mathbf {e} _{B}.} The velocity of

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1632-462: The horse can move with its tongue. Mouthpieces may be smooth, wire-wrapped or otherwise roughened, or of twisted wire or metal. Various types of metal or synthetic substances are used for bit mouthpieces, which may determine how much a horse salivates or otherwise tolerates a bit; a horse having a moist mouth is considered more relaxed and responsive. Commonly used metals include stainless steel and nickel alloys, which generally do not rust and have

1683-454: The horse's head to the rider. The bit applies pressure to the horse's mouth, and reinforces the other control signals from the rider's legs and weight distribution. A well schooled horse needs little pressure on the bit from a skilled rider. Studies have indicated that soft, consistent bit contact between the rider and horse causes the animal less stress than intermittent or unpredictable contact. Although there are hundreds of design variations,

1734-573: The inhabitants only as a food staple. As a part of the Sredny Stog complex, it is considered to be very early Indo-European , and probably, Proto-Indo-European , within the traditional context of the Kurgan hypothesis of Marija Gimbutas , though Sredny Stog is itself pre-kurgan as to burial rite. Mesolithic: Mathieson (2018) analyzed 28 individuals from Deriivka, dated to ca. 7000 BC to 2700 BC. As an example, one male, dated to ca. 7000 to 6700 BC, carried

1785-426: The input force F A is obtained as M A = F B F A = a b , {\displaystyle MA={\frac {F_{B}}{F_{A}}}={\frac {a}{b}},} which is the mechanical advantage of the lever. This equation shows that if the distance a from the fulcrum to the point A where the input force is applied is greater than the distance b from fulcrum to

1836-443: The lips, chin groove and poll. Bits offer varying degrees of control and communication between rider and horse depending upon their design and on the skill of the rider. It is important that the style of bit is appropriate to the horse's needs and is fitted properly for it to function properly and be as comfortable as possible for the horse. All bits work with either direct pressure or leverage. Bits that act with direct pressure on

1887-410: The male studied carried R1b1a1a2a2 . Regarding mtDNA, three individuals carried subclades of U5, while one female carried J2b1 . Bit (horse) The bit is an item of a horse's tack . It usually refers to the assembly of components that contacts and controls the horse's mouth, and includes the shanks, rings, cheekpads and mullen, all described here below, but it also sometimes simply refers to

1938-529: The need for control of horses in warfare drove extensive innovation in bit design, producing a variety of prototypes and styles over the centuries, from Ancient Greece into modern-day use. A bit consists of two basic components, the bit mouthpiece that goes inside the horse's mouth, and the bit rings of a snaffle bit or shanks of a curb bit , to which the bridle and reins attach. All bits act with some combination of pressure and leverage, often in conjunction with pressure applied by other parts of

1989-409: The output force "load" or "resistance". This allows the identification of three classes of levers by the relative locations of the fulcrum, the resistance and the effort: These cases are described by the mnemonic fre 123 where the f fulcrum is between r and e for the 1st class lever, the r resistance is between f and e for the 2nd class lever, and the e effort is between f and r for

2040-399: The output force is applied (point B ), then the lever amplifies the input force. On the other hand, if the distance a from the fulcrum to the input force is less than the distance b from the fulcrum to the output force, then the lever reduces the input force. The use of velocity in the static analysis of a lever is an application of the principle of virtual work . A lever is modeled as

2091-462: The paternal haplogroup R1a and the maternal U5a2a . Five individuals buried at the nearby site of Vasil'evka from ca. 8800 BC to 7500 BC were also analyzed. One male carried the paternal haplogroup R1a, another I2a1 , the third R1b1a . With regard to mtDNA , all individuals surveyed, both male and female, carried subclades of maternal haplogroup U5 . Eighteen Neolithic individuals buried at Deriivka from ca. 5500 BC to 4500 BC were analyzed. Of

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2142-416: The point P that defines the fulcrum be r P , and introduce the lengths a = | r A − r P | , b = | r B − r P | , {\displaystyle a=|\mathbf {r} _{A}-\mathbf {r} _{P}|,\quad b=|\mathbf {r} _{B}-\mathbf {r} _{P}|,} which are the distances from

2193-562: The points A and B are obtained as v A = θ ˙ a e A ⊥ , v B = θ ˙ b e B ⊥ , {\displaystyle \mathbf {v} _{A}={\dot {\theta }}a\mathbf {e} _{A}^{\perp },\quad \mathbf {v} _{B}={\dot {\theta }}b\mathbf {e} _{B}^{\perp },} where e A and e B are unit vectors perpendicular to e A and e B , respectively. The angle θ

2244-452: The poll, chin groove and mouth of the horse are in the category of curb bits . Most curb bit mouthpieces are solid without joints, ranging from a straight bar with a slight arch, called a "mullen" mouthpiece, through a "ported" bit that is slightly arched in the middle to provide tongue relief, to the full spade bit of the Vaquero style of western riding which combines both a straight bar and

2295-411: The same size as metal bits, and some are flavored. Often, bits with shanks that also have single- or double-jointed mouthpieces are incorrectly referred to as snaffles. Because of the presence of a shank, they are actually in the curb bit family. The mouthpiece of the bit does not rest on the teeth of the horse , but rather rests on the gums or "bars" of the horse's mouth in an interdental space behind

2346-423: The sixteen males analyzed, eleven were found to be carriers of R or various subclades of it (particularly R1b1a ), while five carried I and subclades of it ( I2a2a1b , I2a2a and I2a2a1b1 ). In regard to mtDNA , all Neolithic individuals, both male and female, belonged to U (particularly subclades of U5 and U4 ). Fifteen Neolithic individuals buried at the nearby sites of Volniensky, Vilnianka and Vovnigi from

2397-425: The term " bitless bridle " has become a popular colloquialism in recent years. The riders of early domesticated horses probably used some type of bitless headgear made of sinew, leather, or rope. Components of the earliest headgear may be difficult to determine, as the materials would not have held up over time. For this reason, no one can say with certainty which came first, the bitted or the bitless bridle. There

2448-421: The tongue and lips are in the general category of snaffle bits. Snaffle bits most commonly have a single jointed mouthpiece and act with a nutcracker effect on the bars, tongue and occasionally roof of the mouth. However, any bit that operates only on direct pressure is a "snaffle" bit, regardless of mouthpiece. Bits that have shanks coming off the bit mouthpiece to create leverage that applies pressure to

2499-512: The use of a curb chain or curb strap for proper action and safe use. Some bits combine both direct pressure and leverage, the most common examples being the Pelham bit , which has shanks and rings allowing both direct and leverage pressure on a single bit and is ridden with four reins; the Kimblewick or Kimberwicke , a hybrid bit that uses minimal leverage on a modified snaffle-type ring combined with

2550-410: Was a favored material until about 1940, when stainless steel largely replaced it. Copper , aurigan and sweet iron (cold rolled steel) are incorporated into some bits to encourage salivation in the mouth of the horse, which encourages a softer mouth and more relaxed jaw. Bits also can be made of other materials such as rubber or plastic, sometimes in combination with metals. Throughout history,

2601-480: Was invented. Of interest is some apparently equivocal evidence for fenced houses. Two cemeteries are associated, one from the earlier (neolithic) Dnieper-Donets culture and one from the aforementioned Sredny Stog culture, of the Copper Age. The habitation site included three dwellings and six hearths, each containing hundreds of animal bones. Of all the bones, approximately 75% came from horses, possibly exploited by

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