United Kingdom: Parliamentary rejection of May’s plan, May’s survival of a confidence vote, and the Independent Group of breakaway MPs: Meanwhile, in early March, Tom Watson, the deputy leader of the Labour Party, convened a meeting of Labour MPs and members of the House of Lords—many of whom felt that Corbyn had taken the party too far leftward—to consider an alternative vision for the party.

William Watson was an English Roman Catholic priest who was executed for his part in the “Bye Plot” against King James I. At the age of 16 Watson left England for France, where he was ordained priest in April 1586. Returning to England in June of that year, he spent the next 16 years in and out of

electromagnetism: Invention of the Leyden jar: …the appearance of Musschenbroek’s device, William Watson, an English physician and scientist, constructed a more-sophisticated version of the Leyden jar; he coated the inside and outside of the container with metal foil to improve its capacity to store charge. Watson transmitted an electric spark from his device through a wire…

Sir Robert Alexander Watson-Watt was a Scottish physicist credited with the development of radar in England. Watson-Watt attended the University of St. Andrews and later taught at University College, Dundee. From 1915 to 1952 he held a number of government positions, beginning as a meteorologist

Christopher Paul Curtis: …Curtis wrote his first book, The Watsons Go to Birmingham—1963 (1995; TV movie 2013). An early draft of the book won a Jules Hopwood Prize from the University of Michigan, and the published version merited a Newbery Honor Award in 1996.

Jane Austen: Life: In 1804 Jane began The Watsons but soon abandoned it. In 1804 her dearest friend, Mrs. Anne Lefroy, died suddenly, and in January 1805 her father died in Bath.

Watsuji Tetsurō was a Japanese moral philosopher and historian of ideas, outstanding among modern Japanese thinkers who have tried to combine the Eastern moral spirit with Western ethical ideas. (Read Peter Singer’s Britannica entry on ethics.) Watsuji studied philosophy at Tokyo University and

Watt, Absurdist novel by Samuel Beckett, published in 1953. It was written in 1942–44 while Beckett, an early member of the French Resistance, was hiding in southern France from German occupying forces. There is no conventional plot to Watt, nor are there always readily assignable meanings to the

watt, unit of power in the International System of Units (SI) equal to one joule of work performed per second, or to 1746 horsepower. An equivalent is the power dissipated in an electrical conductor carrying one ampere current between points at one volt potential difference. It is named in honour

Watt steam engine, steam engine invented by Scottish engineer James Watt in 1769. The Watt steam engine is considered the first truly efficient steam engine, as it solved the problem of energy wastage through the use of a separate condenser. Watt’s essay about the steam engine for Encyclopædia

Hugh Burgess: …British-born American inventor who, with Charles Watt, developed the soda process used to turn wood pulp into paper.

Houston Texans: Led by sensational defensive end J.J. Watt, the Texans set a franchise record with 12 wins in 2012 but again lost in the divisional round of the following postseason. In 2013 an injury-plagued Texans team swiftly fell from the upper echelons of the AFC and posted a league-worst 2–14 record.…

James Watt was a Scottish instrument maker and inventor whose steam engine contributed substantially to the Industrial Revolution. Watt was also known for patenting the double-acting engine and an early steam locomotive. He was elected fellow of the Royal Society of London in 1785. (Read James

Joachim Vadianus was a Swiss religious reformer and one of the most important native Swiss Humanists. Crowned poet laureate by the Habsburg emperor Maximilian (1514), Vadianus served as rector at the University of Vienna (1516–17) and supervised the publication of the works of various ancient

Dave Grohl: Nirvana: …drummer for bassist and singer-songwriter Mike Watt, backed musician Tom Petty on a Saturday Night Live appearance, and released a CD version of Pocketwatch (1995).

watt-hour meter, device that measures and records over time the electric power flowing through a circuit. Although there are several different types of watt-hour meters, each consists essentially of a small electric motor and a counter. A precise fraction of the current flowing in the circuit is

Marīnid dynasty: …branch of the Marīnids, the Waṭṭāsids (Banū Waṭṭās), assumed rule over Morocco in 1465, but it collapsed when the Saʿdī sharifs took Fès in 1548.

Antoine Watteau was a French painter who typified the lyrically charming and graceful style of the Rococo. Much of his work reflects the influence of the commedia dell’arte and the opéra ballet (e.g., “The French Comedy,” 1716). Antoine Watteau was the son of a roof tiler. According to early

Antoine Watteau was a French painter who typified the lyrically charming and graceful style of the Rococo. Much of his work reflects the influence of the commedia dell’arte and the opéra ballet (e.g., “The French Comedy,” 1716). Antoine Watteau was the son of a roof tiler. According to early

Frisian Islands: …tidal mud flats generally called wadden in Dutch (German: Watten).

Wadden Sea, shallow inlet of the North Sea between the West Frisian Islands and the northern Netherlands mainland. The inlet extends from Noord-Holland to the northeast, where the islands gradually curve toward the mainland and the channel narrows to a few miles. Until the completion of the

Bochum: In 1975 Wattenscheid, a neighbouring city, was united with Bochum, and it serves to some extent as a dormitory suburb for the adjacent industrial complexes of Gelsenkirchen and Essen. Pop. (2003 est.) 387,283.

Calvin and Hobbes: …creating Calvin and Hobbes, cartoonist Bill Watterson (1958– ) drew inspiration from Charles Schulz’s Peanuts and Walt Kelly’s Pogo, among other precursors. He named the main characters for the 16th-century theologian John Calvin and the 17th-century English philosopher Thomas Hobbes. The small central cast of characters remained essentially unchanged throughout…

The Courier-Journal: …Louisville Journal brought about by Henry Watterson, The Courier-Journal’s first editor, who also became a part owner. Watterson was an eloquent writer and a veteran of the Confederate army in the Civil War who greatly admired Abraham Lincoln and who believed in political participation by blacks. His half-century tenure as…

Eospermatopteris, genus of extinct plants known from fossil stumps discovered in the 1870s near Gilboa, New York, U.S. Eospermatopteris trunks were discovered upright, as they would have grown in life, and occurred in dense stands in the marshy lowlands near an ancient inland sea. However, only the

acacia, (genus Acacia), genus of about 160 species of trees and shrubs in the pea family (Fabaceae). Acacias are native to tropical and subtropical regions of the world, particularly Australia (where they are called wattles) and Africa, where they are well-known landmarks on the veld and savanna.

wattle and daub, in building construction, method of constructing walls in which vertical wooden stakes, or wattles, are woven with horizontal twigs and branches, and then daubed with clay or mud. This method is one of the oldest known for making a weatherproof structure. In England, Iron Age sites

basketry: Wattle construction: A single layer of rigid, passive, parallel standards is held together by flexible threads in one of three ways, each representing a different subtype. (1) The bound, or wrapped, type, which is not very elaborate, has a widespread distribution, being used for burden…

bird-of-paradise: …mocha-breasted, bird-of-paradise (Cnemophilus macgregorii); the wattle-billed, or golden-silky, bird-of-paradise (Loboparadisea sericea); and Loria’s, or Lady Macgregor’s, bird-of-paradise (Loria loriae)—three species formerly classified as bowerbirds.

wattle-eye, any of a number of small, stubby African songbirds of the family Platysteiridae; some authorities retain them in the flycatcher subfamily, Muscicapinae. Most species have bright, fleshy eye ornaments, or wattles: in the genus Platysteira they are found above the eyes in both sexes,

wattlebird, any of several New Zealand birds of the family Callaeidae (q.v.); also, a particular name for any honeyeater (q.v.) of the genus

kokako, (species Callaeas cinerea), New Zealand songbird of the family Callaeidae (order Passeriformes). The kokako is 45 cm (17.5 inches) long and has a gray body, black mask, and blue or orange wattles at the corners of the mouth. Surviving in a few mountain forests, the kokako lives mainly on

false sunbird: In the wattled false sunbird (Neodrepanis coruscans), the male is glossy blue above and yellow below, with a large eye wattle; this is lacking in the female, which has dark green upperparts. This species moves slowly and quietly along branches, searching for insects; sometimes (like a true…

Wattrelos, town, Nord département, Hauts-de-France région, northern France, on the Belgian-French border. A northeastern suburb of Roubaix, it has textile, chemical, and metallurgical industries. The community was known as Waterloz in 1030, and the discovery of a golden effigy of Nero in 1864

Watts, southwestern district of Los Angeles, California, U.S. The district, originally called Mud Town, was renamed in 1900 for C.H. Watts, a Pasadena realtor who owned a ranch there. It was annexed to Los Angeles in 1926. The Watts district gained widespread notoriety on August 11–16, 1965, as the

Watts Riots of 1965, series of violent confrontations between Los Angeles police and residents of Watts and other predominantly African American neighbourhoods of South-Central Los Angeles that began August 11, 1965, and lasted for six days. The immediate cause of the disturbances was the arrest of

Watts: A notable local attraction is Watts Towers (now a state historic park and a national historic landmark), a group of 17 bricolage spires constructed from 1921 to 1954 by Italian immigrant Simon Rodia from broken tiles, dishes, rocks, bottles, and seashells; the tallest of the towers rises to nearly 100…

Alan Watts was a British-born American writer, philosopher, and lecturer who is credited with introducing and popularizing Eastern philosophy and religion among Western audiences in the mid-20th century. Watts was widely recognized for his ability to convey ideas and perspectives associated with

Alan Watts was a British-born American writer, philosopher, and lecturer who is credited with introducing and popularizing Eastern philosophy and religion among Western audiences in the mid-20th century. Watts was widely recognized for his ability to convey ideas and perspectives associated with

André Watts was a German-born American pianist who was known for a surpassing technique and understated manner that made him a favored concert performer. Watts was born in Germany, where his father, an African American soldier, was stationed; his mother was a Hungarian refugee and accomplished

the Rolling Stones: …24, 1936, London, England), and Charlie Watts (b. June 2, 1941, London—d. August 24, 2021, London). Later members were Mick Taylor (b. January 17, 1948, Hereford, East Hereford and Worcester, England), Ron Wood (b. June 1, 1947, London), and Darryl Jones (b. December 11, 1961, Chicago, Illinois, U.S.).

House with No Steps: The organization’s driving force was Dorothy Watts and her husband, Lionel Watts, who had struggled to find employment after he became a quadriplegic as a consequence of contracting polio in 1956. Confronted by a lack of understanding in the Sydney community and by the negative attitude that existed towards disabled…

George Frederick Watts was an English painter and sculptor of grandiose allegorical themes. Watts believed that art should preach a universal message, but his subject matter, conceived in terms of vague abstract ideals, is full of symbolism that is often obscure and today seems superficial. Watts

Isaac Watts was an English Nonconformist minister, regarded as the father of English hymnody. Watts, whose father was a Nonconformist, studied at the Dissenting Academy at Stoke Newington, London, which he left in 1694. In 1696 he became tutor to the family of Sir John Hartopp of Stoke Newington (a

J.C. Watts is an American Republican politician who served as a congressman from Oklahoma in the U.S. House of Representatives (1995–2003). Watts first rose to national prominence as a gridiron football star, playing quarterback for the University of Oklahoma Sooners. He led his team to consecutive

Walter Jackson Freeman II: …neurologist who, with American neurosurgeon James W. Watts, was responsible for introducing to the United States prefrontal lobotomy, an operation in which the destruction of neurons and neuronal tracts in the white matter of the brain was considered therapeutic for patients with mental disorders. Freeman’s use of and public advocacy…

Doulton ware: …Lambeth, London, in association with John Watts and known as Doulton and Watts. The company became Doulton and Co. (Ltd.) about 1858 and remained so until the factory closed in 1956.

J.C. Watts is an American Republican politician who served as a congressman from Oklahoma in the U.S. House of Representatives (1995–2003). Watts first rose to national prominence as a gridiron football star, playing quarterback for the University of Oklahoma Sooners. He led his team to consecutive

House with No Steps: …Dorothy Watts and her husband, Lionel Watts, who had struggled to find employment after he became a quadriplegic as a consequence of contracting polio in 1956. Confronted by a lack of understanding in the Sydney community and by the negative attitude that existed towards disabled people, the couple joined with…

Naomi Watts is a British-born Australian actress acclaimed for her subtle performances and eclectic film roles. Her credits included surrealist thrillers such as Mulholland Drive (2001), crime dramas such as 21 Grams (2003), quirky comedies such as I Heart Huckabees (2004), and big-budget

Theodore Watts-Dunton was an English critic and man of letters, who was the friend and, after 1879, protector, agent, and nurse of the poet Algernon Charles Swinburne. Watts studied law and practiced in London, but his real interest was literature. He contributed regularly to the Examiner and was

Theodore Watts-Dunton was an English critic and man of letters, who was the friend and, after 1879, protector, agent, and nurse of the poet Algernon Charles Swinburne. Watts studied law and practiced in London, but his real interest was literature. He contributed regularly to the Examiner and was

Theodore Watts-Dunton was an English critic and man of letters, who was the friend and, after 1879, protector, agent, and nurse of the poet Algernon Charles Swinburne. Watts studied law and practiced in London, but his real interest was literature. He contributed regularly to the Examiner and was

Alexander Wilson: …production, a comic, dramatic ballad, Watty and Meg, was published anonymously; its popularity may have been the result of the belief that the poet Robert Burns was its author. Wilson apparently was never financially successful in publishing verse. In 1792 his satirical writings to aid the cause of the weavers…

Ceram: … (or Goram) Islands, and the Watubela group, all southeast of Ceram. None has hills of more than 1,300 feet (400 metres), and most are thickly wooded. Ceram is covered with tropical forests, the result of a hot climate and heavy rainfall, and excellent timber is produced. The sago palm thrives,…

Tutsi, ethnic group of probable Nilotic origin, whose members live within Rwanda and Burundi. The Tutsi formed the traditional aristocratic minority in both countries, constituting about 9 percent and 14 percent of the population, respectively. The Tutsis’ numbers in Rwanda were greatly reduced by

twist: …example, the frug and the watusi—were invariably performed by shaking the pelvis. In these dances partners only sometimes coordinated their movements. Among the suggested precursors of the twist are included the shimmy and the black bottom, and a song that was popular before 1910 included the lines “Mama, mama, where…

Tutsi, ethnic group of probable Nilotic origin, whose members live within Rwanda and Burundi. The Tutsi formed the traditional aristocratic minority in both countries, constituting about 9 percent and 14 percent of the population, respectively. The Tutsis’ numbers in Rwanda were greatly reduced by

Wau, town, northwestern South Sudan. It lies on the western bank of the Jur River (a tributary of Al-Ghazāl River), about 140 miles (220 km) northwest of Rumbek. The town was the scene of antigovernment disturbances in 1965, in which a number of people were killed and much of Wau was destroyed as a

Wau, town on the island of New Guinea, eastern Papua New Guinea, southwestern Pacific Ocean. The town is situated at the junction of Edie Creek and the Bulolo River, in a mountainous region accessible by road from Lae and by air from Port Moresby. Gold was first discovered (1921) at Koranga Creek,

Juliette Augusta Magill Kinzie: …in her major written work, Wau-bun: The “Early Days” in the North-west (1856), which combined travel accounts and personal experiences of her early years at Fort Winnebago, including the Black Hawk War of 1832, with Native American legends, further early history of Chicago, and particularly the story of John Kinzie.…

Wauchope, town, eastern coastal New South Wales, Australia. It lies about 12 miles (20 km) above the mouth of the Hastings River, just west of Port Macquarie. Wauchope was named for Captain Wauch, an early settler. Its traditional economy was based on lumbering and the manufacture of wood products,

Waucoban Series, lowermost Cambrian rocks (the Cambrian Period lasted from 542 million to 488 million years ago); the name is derived from exposures found at Waucoba Springs, Calif. The period of time corresponding to the rocks of the Waucoban Series is known as the Waucoban Epoch. The Waucoban is

Alfred R. Waud was a British-born American illustrator whose lively and detailed sketches of scenes from the Civil War, which he covered as a press correspondent, captured the war’s dramatic intensity and furnished him with a reputation as one of the preeminent artist-journalists of his era. Waud

Alfred R. Waud was a British-born American illustrator whose lively and detailed sketches of scenes from the Civil War, which he covered as a press correspondent, captured the war’s dramatic intensity and furnished him with a reputation as one of the preeminent artist-journalists of his era. Waud

Mons: Waudru, or Waltrudis, daughter of the Count of Hainaut. During the 9th century, turreted ramparts encircled the small town. Recognized by Charlemagne as the capital of Hainaut (804), it prospered as a cloth-weaving centre between the 14th and the 16th century. Mons, a stronghold and frontier town,…

Alec Waugh was an English popular novelist and travel writer, older brother of the writer Evelyn Waugh. Waugh was educated at Sherborne, from which he was expelled, and the Royal Military Academy at Sandhurst. While only 17, he wrote The Loom of Youth (1917), a novel about public school life that

Alec Waugh was an English popular novelist and travel writer, older brother of the writer Evelyn Waugh. Waugh was educated at Sherborne, from which he was expelled, and the Royal Military Academy at Sandhurst. While only 17, he wrote The Loom of Youth (1917), a novel about public school life that

Evelyn Waugh was an English writer regarded by many as the most brilliant satirical novelist of his day. Waugh was educated at Lancing College, Sussex, and at Hertford College, Oxford. After short periods as an art student and schoolmaster, he devoted himself to solitary observant travel and to the

Evelyn Waugh was an English writer regarded by many as the most brilliant satirical novelist of his day. Waugh was educated at Lancing College, Sussex, and at Hertford College, Oxford. After short periods as an art student and schoolmaster, he devoted himself to solitary observant travel and to the

Mark Waugh is an Australian cricketer who, with his twin brother, Steve, dominated cricket in Australia in the 1990s. Waugh—known as “Junior,” since he was born four minutes after his twin—broke into the Australian Test team as a replacement for his brother, scoring 138 on his debut in 1990.

Mark Waugh is an Australian cricketer who, with his twin brother, Steve, dominated cricket in Australia in the 1990s. Waugh—known as “Junior,” since he was born four minutes after his twin—broke into the Australian Test team as a replacement for his brother, scoring 138 on his debut in 1990.

glassware: United States: …and the sculptor and designer Sidney Waugh, aimed to produce glass with engraved decoration that would rank as fine art. Other noteworthy modern American work included simple designs in blown glass by the Blenko Glass Company of Milton, West Virginia, and enamel patterned bowls by the independent artist Maurice Heaton.…

Steve Waugh is an Australian cricketer who set the record for most international Test appearances (168; later broken by Sachin Tendulkar) and who, with his twin brother, Mark, helped lead the resurgence of the Australian national team in the late 20th century. Waugh made his debut at the age of 20

Steve Waugh is an Australian cricketer who set the record for most international Test appearances (168; later broken by Sachin Tendulkar) and who, with his twin brother, Mark, helped lead the resurgence of the Australian national team in the late 20th century. Waugh made his debut at the age of 20

Waukegan, city, seat (1841) of Lake county, northeastern Illinois, U.S. It lies on a high bluff above Lake Michigan, about 40 miles (65 km) north of Chicago. One of the oldest communities in the state, it was originally a Potawatomi Indian settlement. It was visited by the French explorer Jacques

Waukesha, city, seat (1846) of Waukesha county, southeastern Wisconsin, U.S. It is situated on the Fox River, about 15 miles (25 km) west of Milwaukee. The site was settled by Morris D. Cutler in 1834 near a Potawatomi Indian village and called Prairieville. In 1846 it was renamed Waukesha

Brecon Beacons National Park: …with their highest point at Waun Fach, elevation 2,660 feet (811 metres). Centrally located within the park, south of Brecon, are the Brecon Beacons (old red sandstone), including Pen y Fan, the highest peak in the park, with an elevation of 2,906 feet (886 metres). To the west lies the…

South American forest Indian: Belief and aesthetic systems: The Waurá women of the upper Xingu are famous for their pots and animal-shaped bowls. Of the historic tribes, the Tapajó of the Amazon had the richest style in ceramics, excelled only by the archaeological remains of the Ilha de Marajó. Among some groups in the…

Wausau, city, seat (1850) of Marathon county, north-central Wisconsin, U.S. It lies on the Wisconsin River, about 90 miles (150 km) northwest of Green Bay. Settled in 1839 as a sawmill town, it was first called Big Bull Falls; by 1850 it had been renamed Wausau (Ojibwa: “Faraway Place”). Wausau is

Brandywine Creek, stream in southeastern Pennsylvania and western Delaware, U.S., rising in two branches in Chester county, Pennsylvania, which join near Coatesville. It flows about 20 miles (32 km) southeast past Chadds Ford and through Delaware to join the Christina River just above its

Wauwatosa, city, western suburb of Milwaukee, Milwaukee county, southeastern Wisconsin, U.S. It lies on the Menomonee River, just north of West Allis. Potawatomi and Menominee Indians were among the early inhabitants of the area. Settled in 1835, the community was at first attached to the township

wave, a ridge or swell on the surface of a body of water, normally having a forward motion distinct from the oscillatory motion of the particles that successively compose it. The undulations and oscillations may be chaotic and random, or they may be regular, with an identifiable wavelength between

Barbara Hepworth: Pieces such as Wave (1943–44) became increasingly open, hollowed out, and perforated, so that the interior space is as important as the mass surrounding it. Her practice, increasingly frequent in her mature pieces, of painting the works’ concave interiors further heightened this effect, while she accented and defined…

wave, propagation of disturbances from place to place in a regular and organized way. Most familiar are surface waves that travel on water, but sound, light, and the motion of subatomic particles all exhibit wavelike properties. In the simplest waves, the disturbance oscillates periodically (see

lee wave: They may produce clouds, called wave clouds, when the air becomes saturated with water vapour at the top of the wave.

extratropical cyclone, a type of storm system formed in middle or high latitudes, in regions of large horizontal temperature variations called frontal zones. Extratropical cyclones present a contrast to the more violent cyclones or hurricanes of the tropics, which form in regions of relatively

analysis: Trigonometric series solutions: …normal mode solutions of the wave equation are superposed, the result is a solution of the form where the coefficients a1, a2, a3, … are arbitrary constants. Euler did not state whether the series should be finite or infinite; but it eventually turned out that infinite series held the key…

wave front, imaginary surface representing corresponding points of a wave that vibrate in unison. When identical waves having a common origin travel through a homogeneous medium, the corresponding crests and troughs at any instant are in phase; i.e., they have completed identical fractions of their

wave function, in quantum mechanics, variable quantity that mathematically describes the wave characteristics of a particle. The value of the wave function of a particle at a given point of space and time is related to the likelihood of the particle’s being there at the time. By analogy with waves

waveguide, any of a class of devices that confines and directs the propagation of electromagnetic waves, such as radio waves, infrared rays, and visible light. Waveguides take many shapes and forms. Typical examples include hollow metallic tubes, coaxial cables, and optical fibres. Hollow metallic

wave mechanics, quantum mechanics, especially that version originally developed (1926) by the Austrian physicist Erwin Schrödinger. See Schrödinger

spectroscopy: Coherent anti-Stokes Raman spectroscopy (CARS): …technique involves the phenomenon of wave mixing, takes advantage of the high intensity of stimulated Raman scattering, and has the applicability of conventional Raman spectroscopy. In the CARS method two strong collinear laser beams at frequencies ν1 and ν2 (ν1 > ν2) irradiate a sample. If the frequency difference, ν1…

wave motion, propagation of disturbances—that is, deviations from a state of rest or equilibrium—from place to place in a regular and organized way. Most familiar are surface waves on water, but both sound and light travel as wavelike disturbances, and the motion of all subatomic particles exhibits

wavenumber, a unit of frequency, often used in atomic, molecular, and nuclear spectroscopy, equal to the true frequency divided by the speed of the wave and thus equal to the number of waves in a unit distance. In the case of light, the frequency, symbolized by the Greek letter nu (ν), of any wave

glacier: Surface features: Called wave ogives (pointed arches), these arcs result from the great stretching of the ice in the rapidly flowing icefall. The ice that moves through the icefall in summer has more of its surface exposed to melting and is greatly reduced in volume compared with the…

running-dog pattern, in classical architecture, decorative motif consisting of a repeated stylized convoluted form, something like the profile of a breaking wave. This pattern, which may be raised above, incised into, or painted upon a surface, frequently appears on a frieze, the middle element of

mathematics: Mathematical physics: …and observables, with its mysterious wave packets that were sometimes like particles and sometimes like waves depending on how they were observed, went very neatly into the theory of Hilbert spaces. Functional analysis has ever since grown with the fortunes of particle physics.

wave power, a form of renewable energy in which electricity is generated by harnessing the up-and-down motion of ocean waves. Wave power is typically produced by floating turbine platforms or buoys that rise and fall with the swells. However, wave power can be generated by exploiting the changes in

wave motion, propagation of disturbances—that is, deviations from a state of rest or equilibrium—from place to place in a regular and organized way. Most familiar are surface waves on water, but both sound and light travel as wavelike disturbances, and the motion of all subatomic particles exhibits