Meantone temperament is a musical temperament, a tuning system, obtained by compromising the fifths in order to improve the thirds. Meantone temperaments are constructed the same way as Pythagorean tuning, as a stack of equal fifths, but in meantone each fifth is narrow compared to the perfect fifth of ratio 3:2. Equal temperament, obtained by making all semitones the same size, each equal to one-twelfth of an octave (with ratio the 12th root of 2 to one, narrows the fifths by about 2 cents or 1/12 of a Pythagorean comma, produces thirds that are only better than in Pythagorean tuning. Equal temperament is the same as 1/11 comma meantone tuning. Quarter-comma meantone, which tempers the fifths by 1/4 comma, is the best known type of meantone temperament, the term meantone temperament is used to refer to it specifically. Four ascending fifths tempered by 1/4 comma produce a perfect major third, one syntonic comma narrower than the Pythagorean third that would result from four perfect fifths.

Quarter-comma meantone has been practiced from the early 16th century to the end of the 19th. In third-comma meantone, the fifths are tempered by 1/3 comma, three descending fifths produce a perfect minor third one syntonic comma wider than the Pythagorean one that would result from three perfect fifths. Third-comma meantone can be approximated by a division of the octave in 19 equal steps; the name "meantone temperament" derives from the fact that all such temperaments have only one size of the tone, while just intonation produces a major tone and a minor one, differing by a syntonic comma. In any regular system the tone is reached after two fifths, while the major third is reached after four fifths: the tone therefore is half the major third; this is one sense. In the case of quarter-comma meantone, in addition, where the major third is made narrower by a syntonic comma, the tone is half a comma narrower than the major tone of just intonation, or half a comma wider than the minor tone: this is another sense in which the tone in quarter-tone temperament may be considered a mean tone, it explains why quarter-comma meantone is considered the meantone temperament properly speaking.

"Meantone" can receive the following equivalent definitions: The meantone is the geometric mean between the major whole tone and the minor whole tone. The meantone is the mean of its major third; the family of meantone temperaments share the common characteristic that they form a stack of identical fifths, the tone being the result of two fifths minus one octave, the major third of four fifths minus two octaves. Meantone temperaments are described by the fraction of the syntonic comma by which the fifths are tempered: quarter-comma meantone, the most common type, tempers the fifths by ​1⁄4 of a syntonic comma, with the result that four fifths produce a just major third, a syntonic comma lower than a Pythagorean major third. A meantone temperament is a linear temperament, distinguished by the width of its generator, as shown in the central column of Figure 1. Notable meantone temperaments, discussed below, occupy a narrow portion of this tuning continuum, with fifths ranging from 695 to 699 cents.

While the term meantone temperament refers to the tempering of 5-limit musical intervals, temperaments that approximate 5-limit intervals well, such as Quarter-comma meantone, can approximate 7-limit intervals well, defining septimal meantone temperament. In Figure 1, the valid tuning ranges of 5-limit, 7-limit, 11-limit tunings are shown, can be seen to include many notable meantone tunings. Meantone temperaments can be specified in various ways: by what fraction of a syntonic comma the fifth is being flattened, what equal temperament has the meantone fifth in question, the width of the tempered perfect fifth in cents, or the ratio of the whole tone to the diatonic semitone; this last ratio was termed "R" by American composer and theoretician Easley Blackwood, but in effect has been in use for much longer than that. It is useful because it gives us an idea of the melodic qualities of the tuning, because if R is a rational number N/D, so is 3R + 1/5R + 2 or 3N + D/5N + 2D, the size of fifth in terms of logarithms base 2, which tells us what division of the octave we will have.

If we multiply by 1200, we have the size of fifth in cents. In these terms, some notable meantone tunings are listed below; the second and fourth column are corresponding approximations to the first column. The third column shows how close the second column's approximation is to the actual size of the fifth interval in the given meantone tuning from the first column. Neither the just fifth nor the quarter-comma meantone fifth is a rational fraction of the octave, but several tunings exist which approximate the fifth by such an interval. Equal temperaments useful as meantone tunings include 19-ET, 50-ET, 31-ET, 43-ET, 55-ET; the farther the tuning gets away from quarter-comma meantone, the less related the tuning is to harmonic timbres, which can be overcome by tempering the partials to match the tuning –, possible, only on

The Hinckley Hill Historic District encompasses a well-preserved collection of stylish mid-19th century residences in Calais, Maine. Built between 1820 and 1860, it includes a trio of high-quality Gothic Revival houses from the 1850s near the eastern edge of the town; the district was listed on the National Register of Historic Places in 1994. The Hinckley Hill area is located on River Road, the eastward extension of Main Street beyond the central town grid; the district includes five properties on the south side of River Road, just east of Franklin Street, another five on the north side, extending eastward from just opposite the last of the southern five. All are residential properties with 1-1/2 to 2-1/2 stories in height; the oldest house is a c. 1820 Cape with Federal style decoration, while the most recent historic property is an early 20th century Colonial Revival house. Two houses built after 1950 are not significant; the most visually distinctive of the district's houses are a trio of Gothic Revival buildings on the north side of River Road.

Built between 1850 and 1855, they are among the town's most architecturally sophisticated buildings, constructed at a time when the town still had a frontier feel to it. Of these, the George Washburn House and the Alexander Gilmore House are both individually listed on the National Register for their architecture; the Gilmore House is one of two with a known architect: it was designed by New Brunswick architect Matthew Stead. National Register of Historic Places listings in Washington County, Maine

Irregular military is any non-standard military component, distinct from a country's national armed forces. Being defined by exclusion, there is significant variance in, it can refer to the type of tactics used. An irregular military organization is one, not part of the regular army organization. Without standard military unit organization, various more general names are used. Irregulars are soldiers or warriors that are members of these organizations, or are members of special military units that employ irregular military tactics; this applies to irregular troops, irregular infantry and irregular cavalry. Irregular warfare is warfare employing the tactics used by irregular military organizations; this involves avoiding large-scale combat, focusing on small, stealthy and run engagements. The words "regular" and "irregular" have been used to describe combat forces for hundreds of years with little ambiguity; the requirements of a government's chain of command cause the regular army to be well defined, anybody fighting outside it, other than official paramilitary forces, are irregular.

In case the legitimacy of the army or its opponents is questioned, some legal definitions have been created. In international humanitarian law, the term "irregular forces" refers to a category of combatants that consists of individuals forming part of the armed forces of a party to an armed conflict, international or domestic, but not belonging to that party's regular forces and operating inside or outside of their own territory if the territory is under occupation; the Third Geneva Convention of 1949 uses "regular armed forces" as a critical distinction. The International Committee of the Red Cross is a non-governmental organization responsible for and most associated with the drafting and successful completion of the Third Geneva Convention Relative to the Treatment of Prisoners of War; the ICRC provided commentary saying that "regular armed forces" satisfy four Hague Conventions conditions. In other words, "regular forces" must satisfy the following criteria: being commanded by a person responsible for his subordinates to a party of conflict having a fixed distinctive emblem recognizable at a distance carrying arms conducting operations in accordance with the laws and customs of warBy extension, combat forces that do not satisfy these criteria are termed "irregular forces".

The term "irregular military" describes the "how" and "what", but it is more common to focus on the "why" as just about all irregular units were created to provide a tactical advantage to an existing military, whether it was privateer forces harassing shipping lanes against assorted New World colonies on behalf of their European contractors, or Auxiliaries, levies and other standing irregular troops that are used as more expendable supplements to assist costly trained soldiers. Bypassing the legitimate military and taking up arms is an extreme measure; the motivation for doing so is used as the basis of the primary label for any irregular military. Different terms come into and out of fashion, based on political and emotional associations that develop. Here is a list of such terms, organized more or less from oldest to latest: Auxiliaries – foreign or allied troops supplementing the regular army, organized from provincial or tribal regions. In the Imperial Roman army, it became common to maintain a number of auxiliaries about equal to the legionaries.

Levies – feudal peasants and freemen liable to be called up for short-term military duty. Privateer – a "for-profit" private person or ship authorized and sponsored by a government by letters of marque to attack foreign vessels during wartime and to destroy or disrupt logistics of the enemy during "peacetime" on the open sea by attacking its merchant shipping, rather than engaging its combatants or enforcing a blockade against them. Revolutionary – someone part of a revolution, whether military or not. Guerrilla – someone who uses unconventional military tactics; the term tends to refer to groups engaged in open conflict, rather than underground resistance. It was coined during the Peninsula War in Spain against France. Montoneras – they were a type of irregular forces that were formed in the 19th century in Latin America. Franc-tireur – French irregular forces during the Franco-Prussian War; the term is used in international legal cases as a synonym for unprivileged combatant. Militia – military force composed of ordinary citizens.

Ordenanças – The Portuguese territorial militia system from the 16th century to the 19th century. It served as local defense force and as the mobilization system that provided conscripts for the first and second lines of the Army. Partisan – In the 20th century, someone part of a resistance movement. In the 18th and 19th century, a local conventional military force using irregular tactics. Used to refer to resistance movements against the Axis Powers during the Second World War. Freedom fighter – A type of irregular military in which the main cause, in their or their supporters' view, is freedom for themselves or others. Paramilitary – Non-regular Armed Force with a claim to official status. Terrorist – An irregular military that targets civilians and other non-combatants to gain political leverage; the term is always used pejoratively and is, like the term "freedom fighter" subjective. False flag or pseudo-operations – Troops of one side dressing like troops of another side to eliminate or discredit the latter and its support, such as members of the Panzer Brigad

"Dancing with Death" was the satirical term used by US Air Force combat pilots to describe evasive maneuvering while facing advanced Soviet surface-to-air missiles over Vietnam. At the onset of the Vietnam War, US pilots had carte blanche over Vietnamese airspace. During the initial stages of the conflict, poorly equipped Vietnamese air defense forces were unable to shoot down high altitude US aircraft using World War II-vintage guns; when they asked for assistance, their chief ally, the Soviet Union, was apprehensive but decided to supply S-75 Dvina SAM systems. About 1000 Soviet specialists arrived Vietnam in April 1965. Generous and massive Soviet military aid, consisting of SAMs, MiG fighters, Kalashnikov rifles, enabled Vietnam to become a formidable belligerent. In the initial stages of the conflict, US combat pilots referred anti-aircraft missiles as Russian-made "telephone poles." However, the S-75 missile gained attention in 1960 when it was used to shoot down U-2 of Francis Gary Powers overflying the Soviet Union, again when, during Cuban Missile Crisis, a S-75 system shot down another U-2.

The situation changed drastically after the introduction of sophisticated Soviet Anti-aircraft systems. 7658 missiles and 95 S-75 Missile Systems were delivered between 1965 and 1972. Most of the systems were extensively deployed in the periphery of the Hanoi-Haiphong area and US intelligence and reconnaissance flights detected the employment of S-75 systems immediately by 5 April 1965, it was in August 1965. During the first few days US pilots were helpless but soon they crafted tactics to dodge anti-aircraft missile systems; the aggressive missile evading maneuvers and tactics were jokingly refereed as "Dancing with Death." The pilots had only few seconds to react and failure meant certain death. To avoid being hit, pilots would employ high-G turns, low level flying, turning toward the sun. American commanders were surprised and impressed that Vietnam, deemed to be a pastoral state, could operate such advanced SAM systems. Americans not only devised tactics but decided to suppress the threat caused by Soviet-supplied anti-aircraft systems.

They created special units armed with AGM-45 Shrike anti-radiation missile designed to home in on hostile anti-aircraft radar, special units, named Wild Weasels, to use the new weapon systems and tactics. The launch platforms of these missiles were the A-4 Skyhawk, A-6 Intruder, F-105 Thunderchief, F-4 Phantom II aircraft. Soviet specialist upgraded S-75 systems on periodic basis and improved its resistance to jamming

Trinity Episcopal Church is a historic church at 317 Franklin Street in Clarksville, Tennessee. The church and its rectory are listed on the National Register of Historic Places as Trinity Church and Rectory; the Trinity Episcopal parish is one of the five oldest Episcopal parishes in Tennessee, established in 1832. Its first church building was completed in 1838, it was the second permanent church building in Clarksville, preceded only by a Methodist church built a few years earlier. The church remained open including the Union Army occupation of Clarksville, its rector, the Rev'd Samuel Ringgold, convinced Union leaders to allow it to remain open, telling them that the value of "decent and orderly" worship should transcend both politics and war. The original building was demolished in 1873 and replaced by the current Romanesque-style building, completed in 1877 and is faced with rough-cut gray stone; the rectory was built in 1883 and a parish house was added in 1916. Renovations in the 1920s and 1980s maintained the historic integrity of the original design.

Trinity Church and Rectory were added to the National Register in 1982. A tornado on January 22, 1999, destroyed the parish house, knocked over part of the steeple and damaged the church roof. Subsequently, the church building was restored and a new parish house was built. Trinity Episcopal Parish website

A rack is a piece of equipment, used to place billiard balls in their starting positions at the beginning of a pocket billiards game. Rack may be used as a verb to describe the act of setting billiard balls in their starting positions, or as a noun to describe a set of balls that are in their starting positions. Traditional racks are in the form of triangular frames made from wood, plastic or metal. A modern variation, called a template rack, is made from a thin material that contains precision cut-outs to hold the balls in place. Purported benefits of template racks include a more consistent racking, their popularity has warranted specific inclusion in profession rules. Unlike traditional racks, template racks are left on the table during the break shot and removed at the players' earliest convenience. For this reason, template racks are never used for games where it is common to slow-break since it is more that the rack will interfere with slow-rolling balls; the most common shape of a rack is that of an equilateral triangle.

Triangular racks are used for eight-ball, straight pool, one-pocket, bank pool and many other games. Diamond-shaped frames are sometimes used for the game of nine-ball and template racks come in a variety of shapes. In eight-ball, 15 object balls are used. Under the Billiard Congress of America's |title=Play 8 Ball Pool Game Online For Free 2019|World Standardized Rules: 8-Ball|date=Nov 2019 |bot=InternetArchiveBot |fix-attempted=yes }} it is prescribed that: The 8 ball must be in the center of the rack; the first ball must be placed at the apex position. The two corner balls must be a solid. All balls other than the 8 ball are placed at random, but in conformance with the preceding corner ball rule; the balls should be pressed together without gaps, as this allows the best break possible. In amateur eight-ball play, in contradistinction to the official rules, a racking variant, followed is: The outer edges of the triangle must be in the pattern of solid, solid, etc.. Sometimes, the balls must be placed in numeric order from the top of the triangle down and from left to right, i.e. the 1 on the foot spot, followed by the 2 3 in the second row, so on.

This always results in the corner balls of the rack being both stripes. In nine-ball, the basic principles are the same as detailed in the eight-ball section above, but only balls 1 through 9 are used; some players place the balls for the 9 ball. However, all balls other than the 1 and 9 may be randomly placed. Note that racking in numeric order in nine-ball, unlike in eight-ball, does not result in a contravention of the official rules. In nine-ball games where a handicap is given by one player being spotted a ball, some tournament venues enforce a rule that the spotted ball must be racked as one of the two balls in the row directly behind the 1 ball. In the initial rack in straight pool, fifteen balls are racked in a triangular rack, with the center of the apex ball placed over the foot spot; this rule developed because the color and pattern of the 1 and 5 balls are thought to provide maximum contrast with the end rails and are the balls targeted on straight pool's exacting standard break. All other balls are placed at random.

Straight pool is played to a specific number of points agreed on prior to the match's start, with each pocketed ball being worth one point to the shooter. Because the game is played to a number of points far in excess of the fifteen points total available in the initial rack, multiple intragame racks are necessary. Intragame racking employs a separate set of rules from those in place at the game's start. After the initial rack, the balls are played until only the cue ball and one object ball remain on the table's surface. At that time, the fourteen pocketed balls are racked with no apex ball, the rack is so placed so that if the apex ball were in the rack, its center would rest directly over the table's foot spot. Play continues with the cue ball shot from where it rested and the fifteenth ball from where it rested prior to racking. A number of rules have developed which detail what must be done when one or both of the cue ball and fifteenth object ball are either in the rack area at the time an intragame rack is necessary, or are in such close proximity to the intragame racking area, that the physical rack cannot be used without moving the one or the other.

The rules vary depending on whether the cue ball or fifteenth ball are resting on the table's head spot. Such rules are detailed on the following chart. In both one-pocket and bank pool all fifteen object balls are racked at random, with the center of t