Ignition coil
An ignition coil is an induction coil in an automobile's ignition system that transforms the battery's low voltage to the thousands of volts needed to create an electric spark in the spark plugs to ignite the fuel. Some coils have an internal resistor, while others rely on a resistor wire or an external resistor to limit the current flowing into the coil from the car's 12-volt supply; the wire that goes from the ignition coil to the distributor and the high voltage wires that go from the distributor to each of the spark plugs are called spark plug wires or high tension leads. Every ignition coil system required mechanical contact breaker points and a capacitor. More recent electronic ignition systems use a power transistor to provide pulses to the ignition coil. A modern passenger automobile may use one ignition coil for each engine cylinder, eliminating fault-prone spark plug cables and a distributor to route the high voltage pulses. Ignition systems are not required for diesel engines which rely on compression to ignite the fuel/air mixture.
An ignition coil consists of a laminated iron core surrounded by two coils of copper wire. Unlike a power transformer, an ignition coil has an open magnetic circuit — the iron core does not form a closed loop around the windings; the energy, stored in the magnetic field of the core is the energy, transferred to the spark plug. The primary winding has few turns of heavy wire; the secondary winding consists of thousands of turns of smaller wire, insulated from the high voltage by enamel on the wires and layers of oiled paper insulation. The coil is inserted into a metal can or plastic case with insulated terminals for the high voltage and low voltage connections; when the contact breaker closes, it allows current from the battery to flow through the primary winding of the ignition coil. The current does not flow because of the inductance of the coil. Current flowing in the coil produces a magnetic field in the core and in the air surrounding the core; the current must flow long enough to store enough energy in the field for the spark.
Once the current has built up to its full level, the contact breaker opens. Since it has a capacitor connected across it, the primary winding and the capacitor form a tuned circuit, as the stored energy oscillates between the inductor formed by the coil and the capacitor, the changing magnetic field in the core of the coil induces a much larger voltage in the secondary of the coil. More modern electronic ignition systems operate on the same principle, but some rely on charging the capacitor to around 400 volts rather than charging the inductance of the coil; the timing of the opening of the contacts must be matched to the position of the piston in the cylinder so that the spark may be timed to ignite the air/fuel mixture to extract the most angular momentum possible. This is several degrees before the piston reaches top dead center; the contacts are driven off a shaft, driven by the engine camshaft, or, if electronic ignition is used, a sensor on the engine shaft controls the timing of the pulses.
The amount of energy in the spark required to ignite the air-fuel mixture varies depending on the pressure and composition of the mixture, on the speed of the engine. Under laboratory conditions as little as 1 millijoule is required in each spark, but practical coils must deliver much more energy than this to allow for higher pressure, rich or lean mixtures, losses in ignition wiring, plug fouling and leakage; when gas velocity is high in the spark gap, the arc between the terminals is blown away from the terminals, making the arc longer and requiring more energy in each spark. Between 30 and 70 milli-joules are delivered in each spark. Ignition coils were made with varnish and paper insulated high-voltage windings, inserted into a drawn-steel can and filled with oil or asphalt for insulation and moisture protection. Coils on modern automobiles are cast in filled epoxy resins which penetrate any voids within the winding. A modern single-spark system has one coil per spark plug. To prevent premature sparking at the start of the primary pulse, a diode or secondary spark gap is installed in the coil to block the reverse pulse that would otherwise form.
In a coil meant for a dual-spark system, the secondary winding has two terminals isolated from the primary, each terminal connects to a spark plug. With this system, no extra diode is needed since there would be no fuel-air mixture present at the inactive spark plug. In a low-inductance coil, fewer primary turns are used, so primary current is higher; this is not compatible with the capacity of mechanical breaker points, so solid-state switching is used. Early gasoline internal combustion engines used a magneto ignition system, since no battery was fitted to the vehicle; the voltage produced by a magneto is dependent on the speed of the engine, making starting difficult. A battery-operated coil can provide a high-voltage spark at low speeds, making starting easier; when batteries became common in automobiles for cranking and lighting, the ignition coil system displaced magneto ignition. In older vehicles, a single coil would serve all the spark plugs via the ignition distributor. Notable exceptions are the Saab 92, some Volkswagens, the Wartburg 353 which have one ignition coil per cylinder.
The flat twin cylinder 1948 Citroën 2CV used one double ended coil without a distributor, just contact breakers, in a wasted spark system. In modern systems, the distributor is omitted and ignition is instead electronically controlled. Much smaller
Figure skating
Figure skating is a sport in which individuals, duos, or groups perform on figure skates on ice. It was the first winter sport included in the Olympics, in 1908; the four Olympic disciplines are men's singles, ladies' singles, pair skating, ice dance. Non-Olympic disciplines include synchronized skating, Theater on Ice, four skating. From juvenile through senior-level competition, skaters perform two programs which, depending on the discipline, may include spins, moves in the field, throw jumps, death spirals, other elements or moves; the blade has a groove on the bottom creating two distinct edges: outside. Judges prefer that skaters glide on one edge of the blade and not on both at the same time, referred to as a flat edge. During a spin, skaters use the "sweet spot" of the blade, formally called a rocker, the roundest portion of the blade, just behind the pick and near the middle of the blade. Skates used in single and pair skating have a set of large, jagged teeth called toe picks on the front of the blade.
Toe picks are used for the take-off on jumps. Ice dance blades have smaller toe picks. Figure skaters compete at various levels from beginner up to the Olympic level at local, regional and international competitions; the International Skating Union competitions. These include the Winter Olympics, the World Championships, the World Junior Championships, the European Championships, the Four Continents Championships, the Grand Prix series, the ISU Challenger Series; the sport is associated with show business. Major competitions conclude with exhibition galas, in which the top skaters from each discipline perform non-competitive programs. Many skaters, both during and after their competitive careers skate in ice shows, which run during the competitive season and the off-season; the term "professional" in skating refers not to skill competitive status. Figure skaters competing at the highest levels of international competition are not "professional" skaters, they are sometimes referred to as amateurs.
Professional skaters include those who have lost their ISU eligibility and those who perform only in shows. They may include former Olympic and World champions who have ended their competitive career as well as skaters with little or no international competitive experience. In languages other than English, Korean, Italian and Russian, figure skating is referred to by a name that translates as "artistic skating." The most visible difference in relation to ice hockey skates is that figure skates have a set of large, jagged teeth called toe picks on the front part of the blade. These are used in jumping and should not be used for stroking or spins. If used during a spin, the toe pick will cause the skater to lose momentum, or move away from the center of the spin. Blades are mounted to the heel of the boot with screws. High-level figure skaters are professionally fitted for their boots and blades at a reputable skate shop. Professionals are employed to sharpen blades to individual requirements. Blades are about 3/16 inch thick.
When viewed from the side, the blade of a figure skate is not flat, but curved forming an arc of a circle with a radius of 180–220 cm. This curvature is referred to as the rocker of the blade; the "sweet spot" is the part of the blade on which all spins are rotated. The blade is "hollow ground"; the inside edge of the blade is on the side closest to the skater. In figure skating, it is always desirable to skate on only one edge of the blade. Skating on both at the same time may result in lower skating skills scores; the effortless power and glide across the ice exhibited by elite figure skaters fundamentally derives from efficient use of the edges to generate speed. Ice dancers' blades are about an inch shorter in the rear than those used by skaters in other disciplines, to accommodate the intricate footwork and close partnering in dance. Dancers' blades have a smaller toe pick as they do not require the large toe pick used for jumping in the other disciplines. Hard plastic skate guards are used when the skater must walk in his or her skates when not on the ice, to protect the blade from dirt or material on the ground that may dull the blade.
Soft blade covers called soakers are used to absorb condensation and protect the blades from rust when the skates are not being worn. In competition, skaters are allowed three minutes to make repairs to their skates. Off-ice training is the term for physical conditioning. Besides regular physical exercise, skaters do walk-throughs of jumps off the ice in order to practice sufficient rotation and height of their jumps, to practice consistency in landing on one foot. There is significant variation in the dimensions of ice rinks. Olympic-sized rinks have dimensions of 30 m × 60 m, NHL-sized rinks are 26 m × 61 m, while European rinks are sometimes 30 m × 64 m; the ISU prefers Olympic-sized rinks for figure skating competitions for major events. According to ISU rule 342, a figure skating rink for an ISU event "if possible, shall measure sixty meters in one direction and thirty meters in the other, but not larger, not less than fifty-six meters in one direct
Cabinet of curiosities
Cabinets of curiosities were notable collections of objects. The term cabinet described a room rather than a piece of furniture. Modern terminology would categorize the objects included as belonging to natural history, ethnography, religious or historical relics, works of art, antiquities; the classic cabinet of curiosities emerged in the sixteenth century, although more rudimentary collections had existed earlier. In addition to the most famous and best documented cabinets of rulers and aristocrats, members of the merchant class and early practitioners of science in Europe formed collections that were precursors to museums; the earliest pictorial record of a natural history cabinet is the engraving in Ferrante Imperato's Dell'Historia Naturale. It serves to authenticate its author's credibility as a source of natural history information, in showing his open bookcases at the right, in which many volumes are stored lying down and stacked, in the medieval fashion, or with their spines upward, to protect the pages from dust.
Some of the volumes doubtless represent his herbarium. Every surface of the vaulted ceiling is occupied with preserved fishes, stuffed mammals and curious shells, with a stuffed crocodile suspended in the centre. Examples of corals stand on the bookcases. At the left, the room is fitted out like a studiolo with a range of built-in cabinets whose fronts can be unlocked and let down to reveal intricately fitted nests of pigeonholes forming architectural units, filled with small mineral specimens. Above them, stuffed birds stand against panels inlaid with square polished stone samples, doubtless marbles and jaspers or fitted with pigeonhole compartments for specimens. Below them, a range of cupboards contain covered jars. In 1587 Gabriel Kaltemarckt advised Christian I of Saxony that three types of item were indispensable in forming a "Kunstkammer" or art collection: firstly sculptures and paintings; when Albrecht Dürer visited the Netherlands in 1521, apart from artworks he sent back to Nuremberg various animal horns, a piece of coral, some large fish fins and a wooden weapon from the East Indies.
The characteristic range of interests represented in Frans II Francken's painting of 1636 shows paintings on the wall that range from landscapes, including a moonlit scene—a genre in itself—to a portrait and a religious picture intermixed with preserved tropical marine fish and a string of carved beads, most amber, both precious and a natural curiosity. Sculpture both classical and secular on the one hand and modern and religious are represented, while on the table are ranged, among the exotic shells: portrait miniatures, gem-stones mounted with pearls in a curious quatrefoil box, a set of sepia chiaroscuro woodcuts or drawings, a small still-life painting leaning against a flower-piece and medals—presumably Greek and Roman—and Roman terracotta oil-lamps, a Chinese-style brass lock, curious flasks, a blue-and-white Ming porcelain bowl; the Kunstkammer of Rudolf II, Holy Roman Emperor, housed in the Hradschin at Prague, was unrivalled north of the Alps. Rudolf's uncle, Ferdinand II, Archduke of Austria had a collection, with a special emphasis on paintings of people with interesting deformities, which remains intact as the Chamber of Art and Curiosities at Ambras Castle in Austria.
"The Kunstkammer was regarded as a microcosm or theater of the world, a memory theater. The Kunstkammer conveyed symbolically the patron's control of the world through its indoor, microscopic reproduction." Of Charles I of England's collection, Peter Thomas states succinctly, "The Kunstkabinett itself was a form of propaganda.". Two of the most famously described seventeenth-century cabinets were those of Ole Worm, known as Olaus Wormius, Athanasius Kircher; these seventeenth-century cabinets were filled with preserved animals, tusks, minerals, as well as other interesting man-made objects: sculptures wondrously old, wondrously fine or wondrously small. They would contain a mix of fact and fiction, including mythical creatures. Worm's collection contained, for example, what he thought was a Scythian Lamb, a woolly fern thought to be a plant/sheep fabulous creature; however he was responsible for identifying the narwhal's tusk as coming from a whale rather than a unicorn, as most owners of these believed.
The specimens displayed were collected during exploring expeditions and trading voyages. In the second half of the 18th century, Belsazar Hacquet operated in Ljubljana the capital of Carniola, a natural history cabinet, appreciated throughout Europe and was visited by the highest nobility, including the Holy Roman Emperor, Joseph II, the Russian grand duke Paul and Pope Pius VI, as well as by famous naturalists, such as Francesco Griselini and Franz Benedikt Hermann, it included a number of minerals, including speci
Musical theatre
Musical theatre is a form of theatrical performance that combines songs, spoken dialogue and dance. The story and emotional content of a musical – humor, love, anger – are communicated through the words, music and technical aspects of the entertainment as an integrated whole. Although musical theatre overlaps with other theatrical forms like opera and dance, it may be distinguished by the equal importance given to the music as compared with the dialogue and other elements. Since the early 20th century, musical theatre stage works have been called musicals. Although music has been a part of dramatic presentations since ancient times, modern Western musical theatre emerged during the 19th century, with many structural elements established by the works of Gilbert and Sullivan in Britain and those of Harrigan and Hart in America; these were followed by the numerous Edwardian musical comedies and the musical theatre works of American creators like George M. Cohan at the turn of the 20th century.
The Princess Theatre musicals and other smart shows like Of Thee I Sing were artistic steps forward beyond revues and other frothy entertainments of the early 20th century and led to such groundbreaking works as Show Boat and Oklahoma!. Some of the most famous musicals through the decades that followed include West Side Story, The Fantasticks, Hair, A Chorus Line, Les Misérables, The Phantom of the Opera, The Producers and Hamilton. Musicals are performed around the world, they may be presented in large venues, such as big-budget Broadway or West End productions in New York City or London. Alternatively, musicals may be staged in smaller venues, such as fringe theatre, Off-Broadway, Off-Off-Broadway, regional theatre, or community theatre productions, or on tour. Musicals are presented by amateur and school groups in churches and other performance spaces. In addition to the United States and Britain, there are vibrant musical theatre scenes in continental Europe, Australasia and Latin America.
Since the 20th century, the "book musical" has been defined as a musical play where songs and dances are integrated into a well-made story with serious dramatic goals, able to evoke genuine emotions other than laughter. The three main components of a book musical are its music and book; the book or script of a musical refers to the story, character development and dramatic structure, including the spoken dialogue and stage directions, but it can refer to the dialogue and lyrics together, which are sometimes referred to as the libretto. The music and lyrics together form the score of a musical and include songs, incidental music and musical scenes, which are "theatrical sequence set to music combining song with spoken dialogue." The interpretation of a musical is the responsibility of its creative team, which includes a director, a musical director a choreographer and sometimes an orchestrator. A musical's production is creatively characterized by technical aspects, such as set design, stage properties and sound.
The creative team and interpretations change from the original production to succeeding productions. Some production elements, may be retained from the original production. There is no fixed length for a musical. While it can range from a short one-act entertainment to several acts and several hours in length, most musicals range from one and a half to three hours. Musicals are presented in two acts, with one short intermission, the first act is longer than the second; the first act introduces nearly all of the characters and most of the music and ends with the introduction of a dramatic conflict or plot complication while the second act may introduce a few new songs but contains reprises of important musical themes and resolves the conflict or complication. A book musical is built around four to six main theme tunes that are reprised in the show, although it sometimes consists of a series of songs not directly musically related. Spoken dialogue is interspersed between musical numbers, although "sung dialogue" or recitative may be used in so-called "sung-through" musicals such as Jesus Christ Superstar, Les Misérables and Hamilton.
Several shorter musicals on Broadway and in the West End have been presented in one act in recent decades. Moments of greatest dramatic intensity in a book musical are performed in song. Proverbially, "when the emotion becomes too strong for speech, you sing. In a book musical, a song is ideally crafted to suit the character and their situation within the story; as The New York Times critic Ben Brantley described the ideal of song in theatre when reviewing the 2008 revival of Gypsy: "There is no separation at all between song and character, what happens in those uncommon moments when musicals reach upward to achieve their ideal reasons to be." Many fewer words are sung in a five-minute song than are spoken in a five-minute block of dialogue. Therefore, there is less time to develop drama in a musical than in a straight play of equivalent length, since a musical devotes more time to music than to dialogue. Within the compressed nature of a musical, the writers must develop the plot; the ma
West End theatre
West End theatre is a common term for mainstream professional theatre staged in the large theatres of "Theatreland" in and near the West End of London. Along with New York City's Broadway theatre, West End theatre is considered to represent the highest level of commercial theatre in the English-speaking world. Seeing a West End show is a common tourist activity in London. Society of London Theatre has announced that 2017 was a record year for the capital’s theatre industry with attendances topping 15,000,000 for the first time since the organization began collecting audience data in 1986. Box office revenues exceeded £700,000,000. Famous screen actors and international alike appear on the London stage. Theatre in London flourished after the English Reformation; the first permanent public playhouse, known as The Theatre, was constructed in 1576 in Shoreditch by James Burbage. It was soon joined by The Curtain. Both are known to have been used by William Shakespeare's company. In 1599, the timber from The Theatre was moved to Southwark, where it was used in building the Globe Theatre in a new theatre district formed beyond the controls of the City corporation.
These theatres were closed in 1642 due to the Puritans who would influence the interregnum of 1649. After the Restoration, two companies were licensed to perform, the Duke's Company and the King's Company. Performances were held in converted buildings, such as Lisle's Tennis Court; the first West End theatre, known as Theatre Royal in Bridges Street, was designed by Thomas Killigrew and built on the site of the present Theatre Royal, Drury Lane. It was destroyed by a fire nine years later, it was replaced by a new structure designed by Christopher Wren and renamed the Theatre Royal, Drury Lane. Outside the West End, Sadler's Wells Theatre opened in Islington on 3 June 1683. Taking its name from founder Richard Sadler and monastic springs that were discovered on the property, it operated as a "Musick House", with performances of opera. In the West End, the Theatre Royal Haymarket opened on 29 December 1720 on a site north of its current location, the Royal Opera House opened in Covent Garden on 7 December 1732.
The Patent theatre companies retained their duopoly on drama well into the 19th century, all other theatres could perform only musical entertainments. By the early 19th century, music hall entertainments became popular, presenters found a loophole in the restrictions on non-patent theatres in the genre of melodrama. Melodrama did not break the Patent Acts; these entertainments were presented in large halls, attached to public houses, but purpose-built theatres began to appear in the East End at Shoreditch and Whitechapel. The West End theatre district became established with the opening of many small theatres and halls, including the Adelphi in The Strand on 17 November 1806. South of the River Thames, the Old Vic, Waterloo Road, opened on 11 May 1818; the expansion of the West End theatre district gained pace with the Theatres Act 1843, which relaxed the conditions for the performance of plays, The Strand gained another venue when the Vaudeville opened on 16 April 1870. The next few decades saw the opening of many new theatres in the West End.
The Criterion Theatre opened on Piccadilly Circus on 21 March 1874, in 1881, two more houses appeared: the Savoy Theatre in The Strand, built by Richard D'Oyly Carte to showcase the comic operas of Gilbert and Sullivan, opened on 10 October, five days the Comedy Theatre opened as the Royal Comedy Theatre on Panton Street in Leicester Square. It abbreviated its name three years later; the theatre building boom continued until about World War I. During the 1950s and 1960s, many plays were produced in theatre clubs, to evade the censorship exercised by the Lord Chamberlain's Office; the Theatres Act 1968 abolished censorship of the stage in the United Kingdom. "Theatreland", London's main theatre district, contains forty venues and is located in and near the heart of the West End of London. It is traditionally defined by The Strand to the south, Oxford Street to the north, Regent Street to the west, Kingsway to the east, but a few other nearby theatres are considered "West End" despite being outside the area proper.
Prominent theatre streets include Drury Lane, Shaftesbury Avenue, The Strand. The works staged are predominantly musicals and modern straight plays, comedy performances. Many theatres in the West End are of late Victorian or Edwardian construction and are owned. Many are architecturally impressive, the largest and best maintained feature grand neo-classical, Romanesque, or Victorian façades and luxurious, detailed interior design and decoration. However, owing to their age, leg room is cramped, audience facilities such as bars and toilets are much smaller than in modern theatres; the protected status of the buildings and their confined urban locations, combined with financial constraints, make it difficult to make substantial improvements to the level of comfort offered. In 2003, the Theatres Trust estimated that an investment of £250 million over the following 15 years was required for modernisation, stated that 60% of theatres had seats from which the stage was not visible; the theatre owners unsuccessfully requested tax concessions to help them meet the costs.
From 2004 onwards there were several incidents of falling plasterwork or performances being cancelled because of urgent building repairs being required. These events culminated in the partial
Broadway theatre
Broadway theatre known as Broadway, refers to the theatrical performances presented in the 41 professional theatres, each with 500 or more seats located in the Theater District and Lincoln Center along Broadway, in Midtown Manhattan, New York City. Along with London's West End theatre, Broadway theatre is considered to represent the highest level of commercial theatre in the English-speaking world; the Theater District is a popular tourist attraction in New York City. According to The Broadway League, for the 2017–2018 season total attendance was 13,792,614 and Broadway shows had US$1,697,458,795 in grosses, with attendance up 3.9%, grosses up 17.1%, playing weeks up 2.8%. The majority of Broadway shows are musicals. Historian Martin Shefter argues that "'Broadway musicals', culminating in the productions of Richard Rodgers and Oscar Hammerstein, became enormously influential forms of American popular culture" and contributed to making New York City the cultural capital of the Western Hemisphere.
New York did not have a significant theatre presence until about 1750, when actor-managers Walter Murray and Thomas Kean established a resident theatre company at the Theatre on Nassau Street, which held about 280 people. They presented Shakespeare ballad operas such as The Beggar's Opera. In 1752, William Hallam sent a company of twelve actors from Britain to the colonies with his brother Lewis as their manager, they established a theatre in Williamsburg and opened with The Merchant of Venice and The Anatomist. The company moved to New York in the summer of 1753, performing ballad operas and ballad-farces like Damon and Phillida; the Revolutionary War suspended theatre in New York, but thereafter theatre resumed in 1798, the year the 2,000-seat Park Theatre was built on Chatham Street. The Bowery Theatre opened followed by others. By the 1840s, P. T. Barnum was operating an entertainment complex in Lower Manhattan. In 1829, at Broadway and Prince Street, Niblo's Garden opened and soon became one of New York's premiere nightspots.
The 3,000-seat theatre presented all sorts of non-musical entertainments. In 1844, Palmo's Opera House opened and presented opera for only four seasons before bankruptcy led to its rebranding as a venue for plays under the name Burton's Theatre; the Astor Opera House opened in 1847. A riot broke out in 1849 when the lower-class patrons of the Bowery objected to what they perceived as snobbery by the upper class audiences at Astor Place: "After the Astor Place Riot of 1849, entertainment in New York City was divided along class lines: opera was chiefly for the upper middle and upper classes, minstrel shows and melodramas for the middle class, variety shows in concert saloons for men of the working class and the slumming middle class."The plays of William Shakespeare were performed on the Broadway stage during the period, most notably by American actor Edwin Booth, internationally known for his performance as Hamlet. Booth played the role for a famous 100 consecutive performances at the Winter Garden Theatre in 1865, would revive the role at his own Booth's Theatre.
Other renowned Shakespeareans who appeared in New York in this era were Henry Irving, Tommaso Salvini, Fanny Davenport, Charles Fechter. Theatre in New York moved from downtown to midtown beginning around 1850, seeking less expensive real estate. In the beginning of the 19th century, the area that now comprises the Theater District was owned by a handful of families and comprised a few farms. In 1836, Mayor Cornelius Lawrence opened 42nd Street and invited Manhattanites to "enjoy the pure clean air." Close to 60 years theatrical entrepreneur Oscar Hammerstein I built the iconic Victoria Theater on West 42nd Street. Broadway's first "long-run" musical was a 50-performance hit called The Elves in 1857. In 1870, the heart of Broadway was in Union Square, by the end of the century, many theatres were near Madison Square. Theatres did not arrive in the Times Square area until the early 1900s, the Broadway theatres did not consolidate there until a large number of theatres were built around the square in the 1920s and 1930s.
New York runs continued to lag far behind those in London, but Laura Keene's "musical burletta" The Seven Sisters shattered previous New York records with a run of 253 performances. It was at a performance by Keene's troupe of Our American Cousin in Washington, D. C. that Abraham Lincoln was shot. The first theatre piece that conforms to the modern conception of a musical, adding dance and original music that helped to tell the story, is considered to be The Black Crook, which premiered in New York on September 12, 1866; the production was five-and-a-half hours long, but despite its length, it ran for a record-breaking 474 performances. The same year, The Black Domino/Between You, Me and the Post was the first show to call itself a "musical comedy". Tony Pastor opened the first vaudeville theatre one block east of Union Square in 1881, where Lillian Russell performed. Comedians Edward Harrigan and Tony Hart produced and starred in musicals on Broadway between 1878 and 1890, with book and lyrics by Harrigan and music by his father-in-law David Braham.
These musical comedies featured characters and situations taken from the everyday life of New York's lower classes and represented a significant step forward from vaudeville and burlesque, towards a more literate form. They starred high quality singers, instead of the women of questionable repute who had starred in earlier m
Isaac Newton
Sir Isaac Newton was an English mathematician, astronomer and author, recognised as one of the most influential scientists of all time, a key figure in the scientific revolution. His book Philosophiæ Naturalis Principia Mathematica, first published in 1687, laid the foundations of classical mechanics. Newton made seminal contributions to optics, shares credit with Gottfried Wilhelm Leibniz for developing the infinitesimal calculus. In Principia, Newton formulated the laws of motion and universal gravitation that formed the dominant scientific viewpoint until it was superseded by the theory of relativity. Newton used his mathematical description of gravity to prove Kepler's laws of planetary motion, account for tides, the trajectories of comets, the precession of the equinoxes and other phenomena, eradicating doubt about the Solar System's heliocentricity, he demonstrated that the motion of objects on Earth and celestial bodies could be accounted for by the same principles. Newton's inference that the Earth is an oblate spheroid was confirmed by the geodetic measurements of Maupertuis, La Condamine, others, convincing most European scientists of the superiority of Newtonian mechanics over earlier systems.
Newton built the first practical reflecting telescope and developed a sophisticated theory of colour based on the observation that a prism separates white light into the colours of the visible spectrum. His work on light was collected in his influential book Opticks, published in 1704, he formulated an empirical law of cooling, made the first theoretical calculation of the speed of sound, introduced the notion of a Newtonian fluid. In addition to his work on calculus, as a mathematician Newton contributed to the study of power series, generalised the binomial theorem to non-integer exponents, developed a method for approximating the roots of a function, classified most of the cubic plane curves. Newton was a fellow of Trinity College and the second Lucasian Professor of Mathematics at the University of Cambridge, he was a devout but unorthodox Christian who rejected the doctrine of the Trinity. Unusually for a member of the Cambridge faculty of the day, he refused to take holy orders in the Church of England.
Beyond his work on the mathematical sciences, Newton dedicated much of his time to the study of alchemy and biblical chronology, but most of his work in those areas remained unpublished until long after his death. Politically and tied to the Whig party, Newton served two brief terms as Member of Parliament for the University of Cambridge, in 1689–90 and 1701–02, he was knighted by Queen Anne in 1705 and spent the last three decades of his life in London, serving as Warden and Master of the Royal Mint, as well as president of the Royal Society. Isaac Newton was born on Christmas Day, 25 December 1642 "an hour or two after midnight", at Woolsthorpe Manor in Woolsthorpe-by-Colsterworth, a hamlet in the county of Lincolnshire, his father named Isaac Newton, had died three months before. Born prematurely, Newton was a small child; when Newton was three, his mother remarried and went to live with her new husband, the Reverend Barnabas Smith, leaving her son in the care of his maternal grandmother, Margery Ayscough.
Newton disliked his stepfather and maintained some enmity towards his mother for marrying him, as revealed by this entry in a list of sins committed up to the age of 19: "Threatening my father and mother Smith to burn them and the house over them." Newton's mother had three children from her second marriage. From the age of about twelve until he was seventeen, Newton was educated at The King's School, which taught Latin and Greek and imparted a significant foundation of mathematics, he was removed from school, returned to Woolsthorpe-by-Colsterworth by October 1659. His mother, widowed for the second time, attempted to make him an occupation he hated. Henry Stokes, master at The King's School, persuaded his mother to send him back to school. Motivated by a desire for revenge against a schoolyard bully, he became the top-ranked student, distinguishing himself by building sundials and models of windmills. In June 1661, he was admitted to Trinity College, Cambridge, on the recommendation of his uncle Rev William Ayscough, who had studied there.
He started as a subsizar—paying his way by performing valet's duties—until he was awarded a scholarship in 1664, guaranteeing him four more years until he could get his MA. At that time, the college's teachings were based on those of Aristotle, whom Newton supplemented with modern philosophers such as Descartes, astronomers such as Galileo and Thomas Street, through whom he learned of Kepler's work, he set down in his notebook a series of "Quaestiones" about mechanical philosophy. In 1665, he discovered the generalised binomial theorem and began to develop a mathematical theory that became calculus. Soon after Newton had obtained his BA degree in August 1665, the university temporarily closed as a precaution against the Great Plague. Although he had been undistinguished as a Cambridge student, Newton's private studies at his home in Woolsthorpe over the subsequent two years saw the development of his theories on calculus and the law of gravitation. In April 1667, he returned in October was elected as a fellow of Trinity.
Fellows were required to become ordained priests, although this was no
