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69-404: Bagpiper may refer to: A person who plays bagpipes Bagpiper (whisky) , a brand of Indian whisky See also [ edit ] List of bagpipers Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title Bagpiper . If an internal link led you here, you may wish to change
138-454: A pan flute played along with a friction drum . Several authors identify the ancient Greek askaulos (ἀσκός askos – wine-skin , αὐλός aulos – reed pipe) with the bagpipe. In the 2nd century AD, Suetonius described the Roman emperor Nero as a player of the tibia utricularis . Dio Chrysostom wrote in the 1st century of a contemporary sovereign (possibly Nero) who could play
207-659: A 13th-century manuscript of northern French origin. Although evidence of bagpipes in the British Isles prior to the 14th century is contested, they are explicitly mentioned in The Canterbury Tales (written around 1380): A baggepype wel coude he blowe and sowne, /And ther-with-al he broghte us out of towne. Bagpipes were also frequent subjects for carvers of wooden choir stalls in the late 15th and early 16th century throughout Europe, sometimes with animal musicians. Actual specimens of bagpipes from before
276-598: A Breton interpretation known as the bagad . The pipe-band idiom has also been adopted and applied to the Galician gaita as well. Bagpipes have often been used in various films depicting moments from Scottish and Irish history; the film Braveheart and the theatrical show Riverdance have served to make the uilleann pipes more commonly known. Bagpipes are sometimes played at formal events at Commonwealth universities, particularly in Canada. Because of Scottish influences on
345-467: A bag, a chanter , and usually at least one drone . Many bagpipes have more than one drone (and, sometimes, more than one chanter) in various combinations, held in place in stocks—sockets that fasten the various pipes to the bag. The most common method of supplying air to the bag is through blowing into a blowpipe or blowstick. In some pipes the player must cover the tip of the blowpipe with the tongue while inhaling, in order to prevent unwanted deflation of
414-480: A closely held trade secret and as such, it had remained unpublished. In the 1970s Garlock, Inc. allegedly infringed Gore's patents by using Cropper's machine and was sued by Gore in the Federal District Court of Ohio . The District Court held Gore's product and process patents to be invalid after a "bitterly contested case" that "involved over two years of discovery , five weeks of trial,
483-564: A constant reservoir of air in the form of a bag. The Great Highland bagpipes are well known, but people have played bagpipes for centuries throughout large parts of Europe , Northern Africa , Western Asia , around the Persian Gulf and northern parts of South Asia . The term bagpipe is equally correct in the singular or the plural, though pipers usually refer to the bagpipes as "the pipes", "a set of pipes" or "a stand of pipes". A set of bagpipes minimally consists of an air supply,
552-653: A distinct class. In the early part of the second millennium, representation of bagpipes began to appear with frequency in Western European art and iconography. The Cantigas de Santa Maria , written in Galician-Portuguese and compiled in Castile in the mid-13th century, depicts several types of bagpipes. Several illustrations of bagpipes also appear in the Chronique dite de Baudoin d’Avesnes ,
621-1150: A long, slow decline that continued, in most cases, into the 20th century. Extensive and documented collections of traditional bagpipes may be found at the Metropolitan Museum of Art in New York City, the International Bagpipe Museum in Gijón , Spain, the Pitt Rivers Museum in Oxford , England and the Morpeth Chantry Bagpipe Museum in Northumberland, and the Musical Instrument Museum in Phoenix, Arizona . The International Bagpipe Festival [ cs ]
690-424: A microporous structure that was about 70% air. It was introduced to the public under the trademark Gore-Tex. Gore promptly applied for and obtained the following patents: Another form of stretched PTFE tape was produced prior to Gore-Tex in 1966, by John W. Cropper of New Zealand . Cropper had developed and constructed a machine for this use. However, Cropper chose to keep the process of creating expanded PTFE as
759-399: A negative Poisson's ratio due to the expansion of ePTFE along all directions, contrasting the more expected reduction in the directions perpendicular to the stress in cases with volume conservation. ePTFE has tunable porosity based on the processing conditions and can be made permeable to certain vapors and gases. However, it is impermeable to most liquids, including water, a property that
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#1732797490680828-547: A part of a bagpipe is a chanter found in 1985 at Rostock , Germany, that has been dated to the late 14th century or the first quarter of the 15th century. The first clear reference to the use of the Scottish Highland bagpipes is from a French history that mentions their use at the Battle of Pinkie in 1547. George Buchanan (1506–82) claimed that bagpipes had replaced the trumpet on the battlefield. This period saw
897-500: A pipe ( tibia , Roman reedpipes similar to Greek and Etruscan instruments) with his mouth as well as by tucking a bladder beneath his armpit. Vereno suggests that such instruments, rather than being seen as an independent class, were understood as variants on mouth-blown instruments that used a bag as an alternative blowing aid and that it was not until drones were added in the European Medieval era that bagpipes were seen as
966-474: A public patent had not been filed, the new form of the material could not be legally recognised. Gore was thereby established as the legal inventor of ePTFE. Following the Gore v. Garlock decision, Gore sued C. R. Bard for allegedly infringing its patent by making ePTFE vascular grafts. Bard promptly settled and agreed to exit the market. Gore next sued IMPRA, Inc., a smaller maker of ePTFE vascular grafts, in
1035-522: Is an airtight reservoir that holds air and regulates its flow via arm pressure, allowing the player to maintain continuous, even sound. The player keeps the bag inflated by blowing air into it through a blowpipe or by pumping air into it with a bellows. Materials used for bags vary widely, but the most common are the skins of local animals such as goats, dogs, sheep, and cows. More recently, bags made of synthetic materials including Gore-Tex have become much more common. Some synthetic bags have zips that allow
1104-455: Is bonded to a fabric. This membrane had about 9 billion pores per square inch (around 1.4 billion pores per square centimeter). Each pore is approximately 1 ⁄ 20,000 the size of a water droplet, making it impenetrable to liquid water while still allowing the more volatile water vapor molecules to pass through. The outer layer of Gore-Tex fabric is coated on the outside with a Durable Water Repellent (DWR) treatment. The DWR prevents
1173-403: Is enabled by the unwinding of PTFE molecules to create large pores within the structure. This favors highly ordered, crystalline PTFE that allows the molecules to disentangle more easily and uniformly when stretched. The porosity is largely determined by the stretching temperature and rate. Changing the stretching rate from 4.8 m/min to 8m/min can increase the porosity from 60.4% to 70.8%. Due to
1242-498: Is exploited in certain applications such as raincoats. These additional properties in combination with the inherent properties of PTFE-based materials more generally (chemical inertness, thermal stability) make ePTFE a versatile material for a range of applications. The most common process used to produce large sheets of ePTFE at scale is a tape stretching process through the following steps: Factors such as strain rate, oven temperature, sintering time, and sintering duration can affect
1311-662: Is held every two years in Strakonice , Czech Republic . During the expansion of the British Empire , spearheaded by British military forces that included Highland regiments , the Scottish Great Highland bagpipe became well known worldwide. This surge in popularity was boosted by large numbers of pipers trained for military service in World War I and World War II . This coincided with a decline in
1380-661: Is known by the name " mezwed ". It is used in the Tunisian pop music genre, also called mezwed , that is named after the instrument. Since the 1960s, bagpipes have also made appearances in other forms of music, including rock, metal, jazz, hip-hop, punk, and classical music, for example with Paul McCartney 's " Mull of Kintyre ", AC/DC 's " It's a Long Way to the Top (If You Wanna Rock 'n' Roll) ", and Peter Maxwell Davies 's composition An Orkney Wedding, with Sunrise . Periodicals covering specific types of bagpipes are addressed in
1449-471: Is leaking when it is not. Wear and cleaning will reduce the performance of Gore-Tex fabric by wearing away this Durable Water Repellent (DWR) treatment. The DWR can be reinvigorated by tumble drying the garment or ironing on a low setting. Gore requires that all garments made from their material have taping over the seams, to eliminate leaks. Gore's sister product, Windstopper , is similar to Gore-Tex in being windproof and breathable, and it can stretch, but it
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#17327974906801518-412: Is nearly inert inside the body. Specifically, expanded polytetrafluoroethylene (E-PTFE) can take the form of a fabric-like mesh. Implementing and applying the mesh form in the medical field is a promising type of technological material feature. In addition, the porosity of Gore-Tex permits the body's own tissue to grow through the material, integrating grafted material into the circulation system. Gore-Tex
1587-412: Is not waterproof. The Gore naming system does not imply any specific technology or material but instead implies a specific set of performance characteristics. Expanded polytetrafluoroethylene is used in clothing due to its breathability and water protection capabilities. Besides use in rainwear ePTFE can now be found in space suits . Gore-Tex is also used internally in medical applications, because it
1656-460: Is smaller than the rest and usually consists of a small tube that is made out of metal or a chicken or duck feather. Uncovering the flea-hole raises any note played by a half step, and it is used in creating the musical ornamentation that gives Balkan music its unique character. Some types of gaida can have a double bored chanter, such as the Serbian three-voiced gajde. It has eight fingerholes:
1725-594: Is structurally between a kaba and dzhura gaida and described as a medium pitched gaida. In Southeastern Europe and Eastern Europe bagpipes known as gaida include: the Albanian : gajde, mishnica, bishnica , Aromanian : gaidã , Bulgarian : гайда ( gaida ), Greek : γκάιντα ( gáida ) τσαμπούνα ( tsaboúna ) or ασκομαντουρα ( askomandoura ), Macedonian : гајда ( gajda ), Serbo-Croatian : gajda/гајда , Turkish : gayda also tulum and Ukrainian : gayda / ґайда . In Tunisia, it
1794-549: Is suitable for use as dance music. Numerous types of bagpipes today are widely spread across Europe, the Middle East and North Africa as well as through much of the former British Empire . The name bagpipe has almost become synonymous with its best-known form, the Great Highland bagpipe , overshadowing the great number and variety of traditional forms of bagpipe. Despite the decline of these other types of pipes over
1863-534: Is used in a wide variety of medical applications, including sutures, vascular grafts, heart patches, and synthetic knee ligaments, which have saved thousands of lives. In the form of expanded polytetrafluoroethylene (E-PTFE), Gore-Tex has been shown to be a reliable synthetic, medical material in treating patients with nasal dorsal interruptions. In more recent observations, expanded polytetrafluoroethylene (E-PTFE) has recently been used as membrane implants for glaucoma surgery . Gore-Tex has been used for many years in
1932-846: The Breton biniou , the Balkan gaida , the Romanian cimpoi , the Black Sea tulum , the Scottish smallpipes and pastoral pipes , as well as other varieties. Bulgaria has the Kaba gaida , a large bagpipe of the Rhodope mountains with a hexagonal and rounded drone, often described as a deep-sounding gaida and the Dzhura gaida with a straight conical drone and of a higher pitch . The Macedonian gaida
2001-542: The International Space Station in November 2015. Traditionally, one of the purposes of the bagpipe was to provide music for dancing. This has declined with the growth of dance bands, recordings, and the decline of traditional dance. In turn, this has led to many types of pipes developing a performance-led tradition, and indeed much modern music based on the dance music tradition played on bagpipes
2070-535: The United States have also adopted the tradition of fielding pipe bands. In recent years, often driven by revivals of native folk music and dance, many types of bagpipes have enjoyed a resurgence in popularity and, in many cases, instruments that had fallen into obscurity have become extremely popular. In Brittany , the Great Highland bagpipe and concept of the pipe band were appropriated to create
2139-399: The tonic note of the chanter). Exceptions are generally those pipes that have a double-chanter instead. A drone is most commonly a cylindrically bored tube with a single reed, although drones with double reeds exist. The drone is generally designed in two or more parts with a sliding joint so that the pitch of the drone can be adjusted. Depending on the type of pipes, the drones may lie over
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2208-435: The 18th century are extremely rare; however, a substantial number of paintings, carvings, engravings, and manuscript illuminations survive. These artefacts are clear evidence that bagpipes varied widely throughout Europe, and even within individual regions. Many examples of early folk bagpipes in continental Europe can be found in the paintings of Brueghel, Teniers, Jordaens, and Durer. The earliest known artefact identified as
2277-668: The Anglo-Norman invasion; another mention attributes their use to Irish troops in Henry VIII's siege of Boulogne . Illustrations in the 1581 book The Image of Irelande by John Derricke clearly depict a bagpiper. Derricke's illustrations are considered to be reasonably faithful depictions of the attire and equipment of the English and Irish population of the 16th century. The "Battell" sequence from My Ladye Nevells Booke (1591) by William Byrd , which probably alludes to
2346-552: The Balkans, and in Southwest Asia. A chanter can be bored internally so that the inside walls are parallel (or "cylindrical") for its full length, or it can be bored in a conical shape. Popular woods include boxwood , cornel , plum or other fruit wood. The chanter is usually open-ended, so there is no easy way for the player to stop the pipe from sounding. Thus most bagpipes share a constant legato sound with no rests in
2415-631: The Irish wars of 1578, contains a piece entitled The bagpipe: & the drone . In 1760, the first serious study of the Scottish Highland bagpipe and its music was attempted in Joseph MacDonald's Compleat Theory . A manuscript from the 1730s by a William Dixon of Northumberland contains music that fits the border pipes , a nine-note bellows-blown bagpipe with a chanter similar to that of the modern Great Highland bagpipe . However,
2484-461: The Northumbrian smallpipes, the piva and the left chanter of the surdelina ) have closed ends or stop the end on the player's leg, so that when the player "closes" (covers all the holes), the chanter becomes silent. A practice chanter is a chanter without bag or drones and has a much quieter reed, allowing a player to practice the instrument quietly and with no variables other than playing
2553-712: The United Kingdom and Commonwealth Nations such as Canada , New Zealand and Australia , the Great Highland bagpipe is commonly used in the military and is often played during formal ceremonies. Foreign militaries patterned after the British army have also adopted the Highland bagpipe, including those of Uganda , Sudan , India , Pakistan , Sri Lanka , Jordan , and Oman . Many police and fire services in Scotland , Canada, Australia, New Zealand, Hong Kong , and
2622-513: The article for that bagpipe Gore-Tex Gore-Tex is W. L. Gore & Associates 's trade name for waterproof, breathable fabric membrane. It was invented in 1969. Gore-Tex blocks liquid water while allowing water vapor to pass through and is designed to be a lightweight, waterproof fabric for all-weather use. It is composed of expanded PTFE (ePTFE), a stretched out form of the PFAS compound polytetrafluoroethylene (PTFE). Gore-Tex
2691-406: The bag, but most blowpipes have a non-return valve that eliminates this need. In recent times, there are many instruments that assist in creating a clean air flow to the pipes and assist the collection of condensation. The use of a bellows to supply air is an innovation dating from the 16th or 17th century. In these pipes, sometimes called " cauld wind pipes ", air is not heated or moistened by
2760-455: The chanter. The term chanter is derived from the Latin cantare , or "to sing", much like the modern French verb meaning "to sing", chanter . A distinctive feature of the gaida's chanter (which it shares with a number of other Eastern European bagpipes) is the "flea-hole" (also known as a mumbler or voicer , marmorka ) which is covered by the index finger of the left hand. The flea-hole
2829-460: The company knew about the dangers of PFOA/PFAS since the 1990s. Gore-Tex materials are typically based on thermo-mechanically expanded PTFE and other fluoropolymer products. They are used in a wide variety of applications such as high-performance fabrics, medical implants , filter media, insulation for wires and cables, gaskets , and sealants. However, Gore-Tex fabric is best known for its use in protective, yet breathable, rainwear . Before
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2898-409: The conservation of illuminated manuscripts . Explosive sensors have been printed on Gore-Tex clothing leading to the sensitive voltametric detection of nitroaromatic compounds. The "Gore-Tex" brand name was formerly used for industrial and medical products. Gore-Tex has been used since the 1980s to make bagpipe (woodwind instrument) bags as an alternative to bags made of animal hides as it
2967-542: The core technology will continue to be based on PTFE, which is a PFAS compound. Many Gore-Tex products have a durable water repellent coating and the version that do not contain PFCs of environmental concerns are marketed as "Gore PFC EC Free DWR". Unlike the "Gore DWR", it lacks any form of oil repellency. The company intends to replace ePTFE membrane with expanded polyethylene membrane by 2025 in consumer fabrics. The new material, while intended to perform comparably to
3036-530: The creation of the ceòl mór (great music) of the bagpipe, which reflected its martial origins, with battle tunes, marches, gatherings, salutes and laments. The Highlands of the early 17th century saw the development of piping families including the MacCrimmonds , MacArthurs, MacGregors , and the Mackays of Gairloch . The earliest Irish mention of the bagpipe is in 1206, approximately thirty years after
3105-547: The existing ePTFE material, will cost more, and require more frequent washing. in 2023, two lawsuits have been filed against Gore on the matter of PFAS related water pollution around its Cecil County, Maryland manufacturing plant and the Maryland Department of the Environment has ordered an investigation and residents in the monitoring area have been offered bottled water. One of the lawsuits alleges that
3174-468: The federal district court in Arizona. IMPRA had a competing patent application for the ePTFE vascular graft. In a nearly decade-long patent/antitrust battle (1984–1993), IMPRA proved that Gore-Tex was identical to prior art disclosed in a Japanese process patent by duplicating the prior art process and through statistical analysis, and also proved that Gore had withheld the best mode for using its patent, and
3243-523: The hide. The simplest methods involve just the use of salt, while more complex treatments involve milk , flour , and the removal of fur. The hide is normally turned inside out so that the fur is on the inside of the bag, as this helps to reduce the effect of moisture buildup within the bag. The chanter is the melody pipe, played with two hands. All bagpipes have at least one chanter; some pipes have two chanters, particularly those in North Africa, in
3312-460: The high work hardening rate of PTFE, ePTFE is significantly stronger than the unstretched material. On a microscopic level, this work hardening corresponds to the increasing crystallinity of PTFE as the fibrils untangle and orient upon the application of an external stress. ePTFE has a strikingly high ultimate tensile strength (50-800 MPa) relative to its full-density counterpart (20-30 MPa) as a result of its high crystallinity. This behavior also yields
3381-443: The introduction of Gore-Tex, the simplest sort of rainwear would consist of a two-layer sandwich, where the outer layer would typically be woven nylon or polyester to provide strength. The inner one would be polyurethane (abbreviated: PU) to provide water resistance, at the cost of breathability. Early Gore-Tex fabric replaced the inner layer of non-breathable PU with a thin, porous fluoropolymer membrane ( Teflon ) coating that
3450-677: The last few centuries, in recent years many of these pipes have seen a resurgence or revival as musicians have sought them out; for example, the Irish piping tradition , which by the mid 20th century had declined to a handful of master players is today alive, well, and flourishing, a situation similar to that of the Asturian gaita , the Galician gaita , the Portuguese gaita transmontana , the Aragonese gaita de boto , Northumbrian smallpipes ,
3519-432: The link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Bagpiper&oldid=1067703604 " Category : Disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Bagpipes Bagpipes are a woodwind instrument using enclosed reeds fed from
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#17327974906803588-482: The main claim of Gore's product patent was declared invalid in 1990. In 1996, IMPRA was purchased by Bard and Bard was thereby able to reenter the market. After IMPRA's vascular graft patent was issued, Bard sued Gore for infringing it. Gore-Tex is used in products manufactured by many different companies. Gore's patents on ePTFE based fabric expired in 1997 and ePTFE membrane waterproof fabrics have become available from other brands. For his invention, Robert W. Gore
3657-514: The main outer layer from becoming wet, which would reduce the breathability of the whole fabric. However, the DWR is not responsible for the jacket being waterproof. Without the DWR, the Gore-Tex layer would become soaked, thus preventing any breathability, and the wearer's sweat being produced on the inside would fail to evaporate, leading to dampness there. This might give the appearance that the fabric
3726-639: The music in Dixon's manuscript varied greatly from modern Highland bagpipe tunes, consisting mostly of extended variation sets of common dance tunes. Some of the tunes in the Dixon manuscript correspond to those found in the early 19th century manuscript sources of Northumbrian smallpipe tunes, notably the rare book of 50 tunes, many with variations, by John Peacock . As Western classical music developed, both in terms of musical sophistication and instrumental technology, bagpipes in many regions fell out of favour because of their limited range and function. This triggered
3795-401: The music. Primarily because of this inability to stop playing, technical movements are made to break up notes and to create the illusion of articulation and accents. Because of their importance, these embellishments (or "ornaments") are often highly technical systems specific to each bagpipe, and take many years of study to master. A few bagpipes (such as the musette de cour, the uilleann pipes ,
3864-484: The octave below and then a drone consonant with the fifth of the chanter. The evidence for bagpipes prior to the 13th century AD is still uncertain, but several textual and visual clues have been suggested. The Oxford History of Music posits that a sculpture of bagpipes has been found on a Hittite slab at Euyuk in Anatolia, dated to 1000 BC. Another interpretation of this sculpture suggests that it instead depicts
3933-406: The player to fit a more effective moisture trap to the inside of the bag. However, synthetic bags still carry a risk of colonisation by fungal spores, and the associated danger of lung infection if they are not kept clean, even if they otherwise require less cleaning than do bags made from natural substances. Bags cut from larger materials are usually saddle-stitched with an extra strip folded over
4002-633: The player's breathing, so bellows-driven bagpipes can use more refined or delicate reeds. Such pipes include the Irish uilleann pipes ; the border or Lowland pipes , Scottish smallpipes , Northumbrian smallpipes and pastoral pipes in Britain; the musette de cour , the musette bechonnet and the cabrette in France; and the Dudy [ pl ] , koziol bialy , and koziol czarny in Poland. The bag
4071-546: The popularity of many traditional forms of bagpipe throughout Europe, which began to be displaced by instruments from the classical tradition and later by gramophone and radio. As pipers were easily identifiable, combat losses were high, estimated at one thousand in World War I. A front line role was prohibited following high losses in the Second Battle of El Alamein in 1943, though a few later instances occurred. In
4140-423: The reed is a combination of a cotton phenolic (Hgw2082) material from which the body of the reed is made and a clarinet reed cut to size in order to fit the body. These type of reeds produce a louder sound and are not so sensitive to humidity and temperature changes. Most bagpipes have at least one drone , a pipe that generally is not fingered but rather produces a constant harmonizing note throughout play (usually
4209-467: The seam and stitched (for skin bags) or glued (for synthetic bags) to reduce leaks. Holes are then cut to accommodate the stocks. In the case of bags made from largely intact animal skins, the stocks are typically tied into the points where the limbs and the head joined the body of the whole animal, a construction technique common in Central Europe . Different regions have different ways of treating
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#17327974906804278-429: The shoulder, across the arm opposite the bag, or may run parallel to the chanter. Some drones have a tuning screw, which effectively alters the length of the drone by opening a hole, allowing the drone to be tuned to two or more distinct pitches. The tuning screw may also shut off the drone altogether. In most types of pipes with one drone, it is pitched two octaves below the tonic of the chanter. Additional drones often add
4347-445: The specific properties of the resulting ePTFE sheet which can be tailored to match particular applications. PTFE is a fluoropolymer made using an emulsion polymerization process that utilizes the fluorosurfactant PFOA , a persistent environmental contaminant. The International Agency for Research on Cancer has classified PFOA as carcinogenic to humans. Gore pledged in 2017 to eliminate PFCs such as PFOA by 2023, although
4416-475: The sport of curling , bagpipes are also the official instrument of the World Curling Federation and are commonly played during a ceremonial procession of teams before major curling championships. Bagpipe making was once a craft that produced instruments in many distinctive, local and traditional styles. Today, the world's largest producer of the instrument is Pakistan , where the industry
4485-542: The testimony of 35 witnesses (19 live, 16 by deposition), and over 300 exhibits" (quoting the Federal Circuit). On appeal, however, the Federal Circuit disagreed in the famous case of Gore v. Garlock , reversing the lower court's decision on the ground, as well as others, that Cropper forfeited any superior claim to the invention by virtue of having concealed the process for making ePTFE from the public. As
4554-759: The top four are covered by the thumb and the first three fingers of the left hand, then the four fingers of the right hand cover the remaining four holes. The note from the chanter is produced by a reed installed at its top. The reed may be a single (a reed with one vibrating tongue) or double reed (of two pieces that vibrate against each other). Double reeds are used with both conical- and parallel-bored chanters while single reeds are generally (although not exclusively) limited to parallel-bored chanters. In general, double-reed chanters are found in pipes of Western Europe while single-reed chanters appear in most other regions. They are made from reed ( arundo donax or Phragmites ), bamboo , or elder . A more modern variant for
4623-457: Was co-invented by Wilbert L. Gore and Gore's son, Robert W. Gore . In 1969, Bob Gore stretched heated rods of polytetrafluoroethylene (PTFE) and created expanded polytetrafluoroethylene (ePTFE). His discovery of the right conditions for stretching PTFE was a happy accident, born partly of frustration. Instead of slowly stretching the heated material, he applied a sudden, accelerating yank. The solid PTFE unexpectedly stretched about 800%, forming
4692-622: Was inducted into the U.S. National Inventors Hall of Fame in 2006. In 2015, Gore was ordered by the Federal Circuit Court of Appeals to pay Bard $ 1 billion in damages. The U.S. Supreme Court declined to review the Federal Circuit's decision. ePTFE has a porous microstructure composed of long, narrow fibrils that intersect at nodes. Increasing the processing temperature or increasing the strain rate leads to more homogenous expansion with more spherically symmetric pores and more intersections between fibrils. The formation of ePTFE
4761-486: Was worth $ 6.8 million in 2010. In the late 20th century, various models of electronic bagpipes were invented. The first custom-built MIDI bagpipes were developed by the Asturian piper known as Hevia (José Ángel Hevia Velasco). Astronaut Kjell N. Lindgren is thought to be the first person to play the bagpipes in outer space , having played " Amazing Grace " in tribute to late research scientist Victor Hurst aboard
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