Church music is music that is intended to be part of Christian worship in churches, chapels,  cathedrals or anywhere Christians meet to worship.  Church music is sacred (religious) music, but not all religious music is church music.  Some music may be inspired by religion, but it may not be church music.  For example, some songs are about religion, but they may not be church music.  Although it uses the words of the Requiem mass,  Verdi's Requiem, was composed for performance in a concert hall.  Britten's War Requiem was written for performance in a cathedral, but it was not meant to be part of a service of worship, so it would not usually be thought of as "church music".

Church music has varied enormously during the history of Christianity as different churches kept changing their ideas about what part music should have in religious worship.  Most church music is based on singing.  Music written for church choirs mostly used the words of the liturgy (the words used in services).  The organ is the most important musical instrument in church music, although from time to time many other instruments have been used as well.

During  many periods in history composers writing for the church used traditional music rather than the newest fashions.  This was particularly the case in the early 17th century when composers such as Claudio Monteverdi often wrote in two different styles: the old style for church music (which, at the time, they called "stilo antico") and the new style for secular (non-religious) music (which they called "stilo moderno").

Music in the early history of the church
During the early history of Christian worship the churches were spread through many countries in the Roman Empire.  The musical traditions that already existed in these countries were used, so there was great variety.  Musical instruments were associated with the devil and with dancing, and so they were thought to be wicked and were not allowed in churches.   The only music that was allowed in churches was singing.  In the 4th century Bishop Ambrosius of Milan introduced the antiphon and encouraged newly composed hymns.  Psalms were an important part of the early Christian worship.  Responsorial psalms were psalms which were sung by one person (who may have been called a "reader"), and the congregation may have responded at the end of a verse with something simple such as "Alleluia".  Gradually "antiphonal psalmody" was developed. This meant that the choir stands on opposite sides facing one another and they sing the verses of the psalm alternately (first one side has a turn, then the other). Antiphonal psalm singing can still be heard today in Anglican cathedrals.

The kind of music heard in the Catholic Church was known as chant or plainchant, often known as "Gregorian chant" (after St Gregory the Great, who was Pope from 590-604).   The text (the words that were sung) were the standard words of the liturgy.  The words of the Mass were set to music by many composers.  Music for the dead was called Requiem Mass. There was also music for Vespers and the Compline.  Until the 16th century the organ was only used to accompany the singing.  In the Renaissance period many great composers such as Giovanni da Palestrina and Orlande de Lassus wrote polyphonic music for the Catholic Church.  They often wrote motets: short pieces based on texts which were not part of the liturgy.

During the period called Reformation some Protestant groups broke away from the Catholic Church.  From this time on Catholic and Protestant music developed in different ways.

Protestant Church Music
Martin Luther started the Protestant movement in Germany.  In the Lutheran church the chorale was the most important part of the musical worship.  Luther himself composed many chorale tunes.  These are like hymns.  The great Johann Sebastian Bach based much of his organ music on the chorale (these pieces are called Chorale Preludes).  The choir often sang a motet.  Sometimes these choir pieces became very long and turned into cantatas.  The words were not from the liturgy but made up by poets or taken from the Bible. Bach wrote about 200 cantatas for the church. He also wrote two great passions which tell the story of Jesus dying on the cross.  Other composers who have contributed to Protestant church music in Europe include Heinrich Schütz, Jan Pieterszoon Sweelinck,  Dietrich Buxtehude, Johann Pachelbel, and Felix Mendelssohn-Bartholdy.

Catholic Church Music
Music for the Catholic Church includes instrumental music such as "church cantatas".  Arcangelo Corelli and Wolfgang Amadeus Mozart wrote many examples of these.  Mozart also wrote several masses.  Great Italian composers of the 16th and 17th centuries who wrote church music include Giovanni Gabrieli and  Claudio Monteverdi.  In the 19th century Rheinberger and  Max Reger wrote music in the Romantic style.  French composers of this time wrote in a style which was similar to secular music.

Church Music in England
When King Henry VIII broke away from the Catholic Church he founded his own church, known as the Anglican church.  Many great composers wrote music for the Anglican service.  Their music for choirs was mostly service settings and anthems.  They also wrote many hymn tunes.  Important composers include  William Byrd (who also wrote Catholic church music) and Thomas Tallis in the Renaissance, Orlando Gibbons and Henry Purcell in the Baroque period, and in later periods Samuel Sebastian Wesley, Charles Stanford, Ralph Vaughan Williams, Edward Bairstow, William Mathias and John Rutter.

Church Music in the United States
Church music in American churches developed, at first, in a similar way to European music.  The Book of Common Prayer was the basis of American worship.  Both Puritans and Baptists thought that congregational singing was important.  In the 18th century Singing Masters from Singing Schools in the north eastern states used to travel around to try to teach people in church to sing properly.  The most famous of these singing masters was William Billings.   Because most people could not read, a system called Lined-out Hymnody developed, in which the priest sang a line and the congregation copied him.  Later in the century, during the "First Great Awakening", the hymn tunes of English composers such as Isaac Watts and Charles Wesley became popular.

In the 19th century people from different churches met at Camp Meetings.  These were led by Evangelists.  The songs reflect the belief that sinners can be saved by repenting.  The music of  black people and of folk music became important influences.  Songs became tuneful and often had refrains.  In the middle of the century Sunday Schools for children became extremely popular and many songs were written for them.  Gospel songs and negro spirituals also became very widely used and influenced the development of church music in America.

The rock and roll music of the 1950s was opposed by many churchs because it was believed to encourage sin. But as churches tried to appeal to more people, they changed by adopting the sounds of this popular style. This became known as contemporary Christian music. As a result of the Jesus movement revival in the latter 1960s and early 1970s, it was originally called Jesus music. "About that time, many young people from the sixties' counterculture began to believe in Jesus.

By the 21st century, many churches of all denominations began to have "contemporary" services in which the new music was performed by a "praise band" using drums and guitars. Often the same church would have a "traditional" service at a different time in which the older hymns were sung.
By this method the church tried to attract people who liked either type of music. Some Christian radio stations also began to use contemporary music, while others kept to the old style of hymns and gospel songs.

Church Music in the Orthodox Church
Church music in the Orthodox Church in East European countries is always sung.  It is based on the Byzantine musical tradition.

Other websites
Catholic church music

Christian music

Church music


A telephone numbering plan is a system used in telecommunications to give telephone numbers to customers and to route telephone calls in a telephone network. A closed numbering plan imposes a fixed length to numbers, such as in North America (10-digit). An open numbering plan may have telephone numbers that vary in length.

A dial plan establishes the type of telephone number in a given area.  This includes country codes, access codes, area codes and all combinations of digits dialed. For instance, the North American public switched telephone network (PSTN) uses a phone numbers with a 3-digit area code and a 7-digit telephone number.

Telephone numbers

Telephone numbering plan


A tenor is a man with a high singing voice. When writing four-part choir music the tenor line will be the third line down, between alto and bass. It is usually written in the treble clef, but will sound an octave lower than written.  Sometimes, it is written in the "C-clef", which is also called a tenor clef.

In opera the role of the young male is usually sung by a tenor.  Depending on characteristics such as: volume, color and style, the tenor voice is classified in following groups:

 The light tenor. This is also called tenor leggero. An example is Peter Pears, who sang the tenor solos in Benjamin Britten's operas.
 The lyric tenor. The lyric tenor is a tenor with a well timbered voice, such as "The Three Tenors" (Luciano Pavarotti, Jose Carreras and Plácido Domingo).
 The spinto tenor. They have special abilities in the high tones, such as Franco Corelli and Enrico Caruso.
 The dramatic tenor. They have a high volume and a dark voice. An example is Mario Del Monaco.

A "Heldentenor" (German for "hero tenor") is someone with a big tenor voice. This is suitable for heroic parts like the heroes in most of Wagner's operas. Lauritz Melchior, Max Lorenz and Jonas Kaufmann are famous heroic tenors.

The Mozart tenor with characteristics including all of the previous mentioned must be able to perform within the strict borders which are laid out by the Mozart style. Anton Dermota, Fritz Wunderlich and Francisco Araiza are the three leading people as Mozart tenor.

In barbershop singing, the tenor part is a harmony part sung predominantly higher than the melody.

Vocal ranges

Tenor


Alcibiades, son of Clinias,  c. 450–404 BC), was a prominent Athenian statesman, orator, and general. He was the last famous member of his mother's aristocratic family, which fell from power after the Peloponnesian War. He played a major role later in that conflict as a strategic advisor, military commander, and politician.

During the course of the Peloponnesian War, Alcibiades changed sides on several occasions. In his native Athens in the early 410s BC, he advocated an aggressive foreign policy, and spoke in favor of an invasion of Sicily. He fled to Sparta after his political enemies brought charges of sacrilege against him.

In Sparta, he served as a strategic adviser, proposing or supervising several major campaigns against Athens. In Sparta too, however, Alcibiades soon made powerful enemies and was forced to defect to Persia. There he served as an adviser to the satrap Tissaphernes until his Athenian political allies brought about his recall. He then served as an Athenian general for several years, but his enemies eventually succeeded in exiling him a second time.

The Sicilian Expedition to Magna Graecia was Alcibiades' idea but his enemies prevented him from commanding. His rival Nicias took command, and the expedition failed disastrously. In the years that he served Sparta, Alcibiades played a role in Athens' undoing; the capture of Decelea and the revolts of several critical Athenian subjects occurred either at his suggestion or under his supervision.

Once restored to his native city, however, he played a crucial role in a string of Athenian victories that eventually brought Sparta to seek a peace with Athens. He favored unconventional tactics, frequently winning cities over by treachery or negotiation rather than by siege.p151 Alcibiades' military and political talents frequently proved valuable to whichever state he worked for. His talent for making powerful enemies ensured that he never remained in one place for long. By the end of the war (which he had helped rekindle in the early 410s) his days of political power were a bygone memory.

In his youth Alcibiades had been a pupil of Socrates. This was something which told against Socrates at his trial.

References

450s BC births
404 BC deaths
Ancient Greek generals
Ancient Greek politicians
People from Athens

Alcibiades


The Hittites were an ancient Armenian people from Anatolia who spoke an Indo-European language.  They wrote with cuneiform script.  They established a kingdom centered at Hattusha in north-central Anatolia from the 18th century BC.

At its peak, the Hittite Empire covered most of modern Turkey and Syria. This was under the reigns of Suppiluliuma I (~1350–1322) and Mursili II (~1321–1295 BC). They had up-and-down relationships with Ancient Egypt to the south, and the Assyrian Empire in Mesopotamia. They were a party to the first known peace treaty, which was made with Ramesses II of Egypt by Hattusili III in 1258 BC.

After 1180 BC, the empire disintegrated into several independent "Neo-Hittite" city-states, some surviving until as late as the 8th century BC.

Empire of Suppiluliuma and Mursili II
The Hittite Kingdom reached its zenith during the reign of Suppiluliuma I (~1350–1322). The kingdom of Mitanni, wracked by civil war, was unable to withstand the Hittite onslaught. Suppiluliuma swiftly attacked the Mitanni heartland, capturing and plundering the Mitanni capital of Washshuganni. He then turned west, recrossed the Euphrates and captured all the Syrian kingdoms which were vassals to the Mitanni, including Aleppo, Mukish, Niya, Qatna, Upi (Upina), and Kadesh. Other kingdoms such as Ugarit and Amurru (an Egyptian vassal) voluntarily became vassal states of the Hittites.

When hostilities flared up once more with Mitanni, Tulipinu, Suppiluliuma's son and viceroy at Aleppo invaded Carchemish but was unable to take the city. Suppiluliuma met with his son and then invaded Syria himself, laying siege to the city of Carchemish. Suppiluliuma broke the siege on the eighth day, installing his son Piyassili as viceroy of the kingdom. With his sons as viceroys of Aleppo and Carchemish, Suppiluliuma had cemented his rule over Syria and brought the empire of Mitanni to an end. The Mitanni King was assassinated soon after.

The murdered prince
When Tutankhamun, the Egyptian Pharaoh died,his widow asked to marry one of Suppiluliuma's sons.  He agreed, and sent his son Zannanza to Egypt to marry the queen.  However, Zannanza was assassinated en route to Egypt. Suppiluliuma was furious and blamed the new Egyptian Pharaoh Ay for his son's death. A Hittite army under crown prince Arnuwanda invaded Egyptian territory from Syria, pillaging and taking many prisoners. These prisoners brought with them a plague which ravaged the Hittite Kingdom continuing well into Mursili's reign and may have killed Suppiluliuma himself.

Mursili II
Mursili II was young and inexperienced, but he proved to be a strong king. In the first years of his reign he carried out punitive campaigns against several kingdoms. In Syria the Nuhashshi king Tette rebelled and was joined by Egyptian troops. Troubles in Syria continued when Mursili's brothers Tulipinu and Piyassili both died. The loss of his Syrian viceroys led to rebellion and even the invasion of Carchemish by Assyria. Leaving his generals to deal with Syria and Haysa, Mursili invaded Carchemish and drove out the Assyrians. Later in his reign Mursili II campaigned against the Kaska once again retaking the Hittite holy city of Niniveh. He also decisively defeating the King of Tummanna.

Other websites

Hattusas/Bogazköy
The Hittite Home Page
Arzawa, to the west, throws light on Hittites
 Pictures of Boğazköy, one of a group of important sites
 Pictures of Yazılıkaya, one of a group of important sites
 Pictures of Alacahöyük, one of a group of important sites
Der Anitta Text (at TITUS)
Encyclopaedia of Turkey : Hittite relief at Karabel
Tahsin Ozguc
Hittites.info
Hittite Period in Anatolia
pictures
Hethitologieportal Mainz, by the Akademie der Wissenschaften, Mainz, corpus of texts and extensive bibliographies on all things Hittite

References

Mesopotamia

Hittites


Mass media are media like radio, television, internet or other things that reach many people.  Television is most used.  We can see and hear  news from around the world.  Radio also brings music and news.  Books supply older and more detailed material.  The internet is also important.  We can search for all the news and information.  Websites like Wikipedia and about.com give information about many things.  Libraries are also important.  In libraries we can read books and listen to music.

The term was coined in the 1920s with the advent of nationwide radio networks, mass-circulation newspapers and magazines, although mass media (like books and manuscripts) were present centuries before the term became common.

Related pages
 Journalism
 Media studies
 Associated Press

Mass media


Humidity means water vapor in the air, but not to liquid droplets in fog, clouds, or rain.  Deserts usually have low humidity, and tropical regions have high humidity. The word "humid" often means that the humidity is high, which gives the feeling of being very damp (wet air), stuffy, or even sweltering when the temperature is also high. When the humidity is low, the air can be said to be "not humid" or "dry."

Higher humidity reduces the effectiveness of sweating in cooling the body by reducing the rate of evaporation of moisture from the skin.

The term "relative humidity" is used to note the amount of humidity as a percent, from 0-100%. Meteorologists use  hygrometers to measure the humidity in the air.

Humidity affects the rate of evaporation. With a higher humidity, the rate of evaporation is less.

Related pages
 Dew point
Relative humidity

Meteorology
Weather measurements

Humidity


Belfast (Irish: Béal Feirste) is the capital of Northern Ireland. It is the second largest city in Ireland, after Dublin. About 270,000 people live in the city. It became capital of Northern Ireland when Northern Ireland was created in 1921. A lot of famous ships were built by the Belfast shipyard Harland and Wolff. In 1911 they built the RMS Titanic.

Capital cities in Europe

Belfast


The pipe organ is a keyboard instrument in which the sound is made by air blowing through pipes. A person who plays the organ is called an organist. The organist plays the instrument using both the hands and the feet. The hands play the keyboards (called manuals), while the feet play pedals which also make notes.

Organs have been made for many centuries. They are usually found in places for Christian worship such as churches and cathedrals, although they may also be found in places like town halls and concert halls or even large private houses. Very small organs can be called "chamber organs". Organs in large churches, cathedrals or halls are very large instruments indeed, and are built especially for the building they are in. They are called "pipe organs" to distinguish them from modern "electronic organs".

No two organs are ever quite the same, and they vary greatly from one country to another and one historical period to another. The information here is about organs from Europe, Great Britain and America.

How an organ works

A description of the organ

In a pipe organ, the musical notes are made by blowing air through pipes. Every organ must have pipes, something to blow the air and a way of controlling which pipes are played.

The pipes are made of metal or wood. They are lined up in rows in the "organ case" which can be as big as a room. The metal pipes are round tubes. They can be made of different types of metal, but the most common type is an alloy (or mixture of metals) of tin and lead called "spotted metal" because it has round shiny spots on it. This alloy makes pipes sound good as the harder tin provides clarity and definition while the softer lead produces tonal warmth. Very small pipes can sometimes be made of silver, like flutes. Some organs also have some pipes made of brass that sound like trumpets. Most organs have a lot of wooden pipes. The wooden pipes have four flat sides and make a sound different from that of the "spotted metal" pipes. They are not usually seen; they are neatly lined up behind the large metal pipes at the front of the organ which are sometimes painted with colours and patterns. All the pipes have to be made with an end that tapers at the bottom where the air blows in.

Each pipe can play only one note which depends on its size. The small pipes play high notes and the large pipes play low notes. Each pipe has its own special sound which depends on the material it is made from (whether it is wood or brass or spotted metal) and on the shape of the pipe. The pipes are arranged in "ranks" so that all the pipes of the same shape and material can be controlled to play a tune together, without all the others.

To blow air through the organ, there are boxes called "wind chests". When the organist is playing, he/she can see a little gauge that tells whether there is enough air. The wind chests can be kept full in two ways. The old-fashioned way is to have an enormous set of "bellows" (see the picture) which are pumped up and down by a person using a large handle. This sucks in air and fills the wind chest. Pumping the bellows of a large pipe organ is heavy work. For this reason, most organs nowadays have an electric motor and a large fan which fills the wind chest.

The organist uses keyboards like those on a piano to play the organ. A small organ may have just one keyboard, but many organs have two keyboards and a very big one may even have five. Organists do not call them keyboards; they call them "manuals". An organist will talk about "a four-manual organ" (which means it is a large one). The manuals are arranged on the organ "console", and the organist sits on a bench in front of the console to play. Apart from the manuals there are two other important parts of the console. There are a set of long wooden pedals which the organist can play with his/her feet. Each pedal plays a different note.

On either side of the manuals there are rows of "stops" which look like knobs. The stops can be pulled out or pushed in. When a stop is pulled out, it turns on some sets of pipes. The organist can choose whether to play loud pipes or soft pipes, flute-sounding pipes or brassy pipes, sweet pipes or harsh-sounding pipes. As the organist plays, he/she does not just have to think about the right notes. He/she also has to think about the sort of "voice" that the organ should play in. He/she can play different ranks of pipes together by pulling out several stops. Some pipes, usually the biggest decorated pipes at the very front of the organ, are used only for the grandest music. By tradition, these pipes are the symbol of the "Voice of God".

When the organist presses the keys of the organ, the sound comes from the air blowing through the pipes. This is because a valve (an opening with a one-way door) opens up to let the air into the pipe, and closes again when the organist stops pressing that key. This can happen in several ways. Traditional organs have what is called a "tracker action". The trackers are thin wooden rods and wires which move backwards and forwards, opening and shutting all the valves. They are worked by levers under the keyboard. A tracker action organ has to have the console right near the organ, usually under the big front pipes.

A more modern development was to have a "tubular pneumatic" action, in which the console could be away from the organ, but connected to it by tubes through which air could be pushed to open the valves. In the most modern pipe organs, the manual is connected to the organ pipes by electric wires. The power to open and shut the valves is controlled by electro-magnetic switches. The console does not have to be close to the organ. This makes it possible for the organist to sit in a position where he/she has good contact with the people in the church, or with other musicians.

The technical details

The manuals
A very small organ may only have one manual (keyboard). Most organs have at least two. In English and American Organs the lower manual is the main one and is called the Great. The upper manual is called the Swell because it operates pipes which are inside a "swell box" which has shutters that can be opened or closed. This makes the music get louder or quieter (crescendo or diminuendo). The organist operates the swell box with a pedal which pivots (rocks to and fro). It is in the centre just above the pedal board. On old English organs the swell box is operated by a lever at the side. This is quite difficult to use. Most of these have now been replaced by central swell boxes.

If there is a third manual, it is called the Choir in English-speaking countries. Originally the English called them "chair organs" because they were a separate instrument. The organist had to turn round and face the other way to play it. It is thought that the word "chair" gradually changed to "choir" because it was often used to accompany the choir. In German organs the third manual was called the "Positiv". The name "Rückpositiv" ("back positive") was used because the pipes were behind the organist's back as he/she sat facing the main organ. These started to become popular again with organ builders in the 1950s when it was felt that the Romantic organ was not suitable for old music, and some organ builders started using Baroque principles again so that the music of composers such as Bach could sound like it used to. The Choir manual is nearest to the player, the Great is in the middle and the Swell is farthest away. The Choir or Positiv often contains soft stops which are suitable for accompanying the choir. On French organs from the late 19th century onwards, the three manuals are arranged differently: the Great ("Grande Orgue") is nearest to the player, the "Positif" is the middle manual and is like a smaller version of the Great, and the Swell ("Recit") is the top manual. This makes it easy for the organist to build up the music, getting louder gradually, by starting at the top and gradually coming down.

The fourth manual is called the Solo because the stops on this manual are used to play out the tune as a solo. This manual is even farther away from the player than the Swell. Large cathedral organs usually have four manuals. The Solo will probably have a very loud stop indeed called the "Tuba" or "Tuba Mirabilis".

If there is a fifth manual it may be called the Echo because it has very quiet stops that echo. Alternatively, especially on American organs, it might be a Bombarde. The Bombarde usually contains loud, bold reed stops, including stops called 'Bombarde'. For instance: a State Trumpet or Pontifical Trumpet might be placed on this manual which can be heard above all the other stops playing. The Bombarde is borrowed from French Organs where it is a standard stop on nearly all the manuals and pedals. Having a Bombarde Manual is something of a luxury for an organist. It can be found, for example, on the organ of Westminster Abbey.

It is extremely unusual to have more than five manuals, but in America there are a few very large organs. The Wanamaker organ at Macy's store in Philadelphia has six manuals. The world's largest organ is in the Atlantic City Convention Hall. It has seven manuals and over 33,000 pipes. However, the largest organ in the world does not work since it would be too expensive to run it.

Using the manuals
Having two or three manuals makes it possible to have quick changes of sound during a piece. The player can also play on two manuals at once: one with the left hand and one with the right. This is particularly useful to make a tune louder than the accompaniment (on a piano this can be done by pressing harder). The manuals can also be coupled together, for example, pulling out the "Swell to Great" stop will make all the sounds from the Swell come out on the Great as well. On an organ with mechanical action the keys of the Swell will be seen "playing by themselves" like a pianola, but on some older organs it can be hard work for the organist's fingers when the manuals are coupled as it makes the action very heavy.

The pedals

The notes on the pedals are arranged like the notes on a keyboard, but are obviously much bigger. The player needs to learn to play by 'feel', otherwise he will have to spend all his time looking at his feet. He plays each note, either with the toe or the heel and either on the inside of the foot or the outside. The American and British Standard organ contains 30 notes giving a range of nearly 2  octaves (C to F, or sometimes C to G: 32 notes). They are not quite in a straight line but fan out a little to make it easier to play (it is called a "radiating, concave pedalboard"). In German and French organs and organs built before 1920, the pedalboard will be straight without any fan curvature to it. Many organists find that this makes it more difficult to play. Organists need a good pair of shoes: ones which have good narrow heels and preferably pointed toes. The soles need to be fairly slippery, but not too much, so that the player can slide the foot from one pedal to another. Organists usually like to keep a pair of shoes which are worn only for playing the organ so that the soles do not have grit or dirt from the street.

The stops
The stops on an organ console give different sounds, like the instruments of an orchestra, and have names which tell the organist what kind of sound they will produce. The stops are usually to the left and right of the organist and they are pulled out ("drawstops" or "pulls" because they are "drawn" i.e. pulled). Some organs have "tab stops" or "rocker stops" which are in front of the player and can be rocked forwards and backwards for on/off.

The stops of an organ can be divided into families.

The chorus stops are the foundation stops, the basic ones which are good for building up the big, solid sound. A diapason or principal is a chorus stop.

The flute stops sound like flutes in an orchestra. They are gentler than the diapasons and sound good for very quick and light music.

The reeds are stops like the oboe, clarinet, trumpet, fagotto, trombone. Each pipe has a reed inside. Their sound is very strong and nasal (like speaking through the nose).

The strings are quiet stops which sound like string instruments. These are stops like the violone and gamba.

There is another way of grouping the stops. Each stop will have a number underneath the name. The number may be 16, 8, 4, 2, 1 or even 2 2/3 or 1 3/5. If the number is 8 this is called an "eight foot stop". This is the normal pitch: the note will sound as it is written, e.g. when playing Middle C the sound will be Middle C. A 4-foot stop will sound an octave higher than written, a 2-foot stop will be two octaves higher. A 16-foot stop will sound an octave lower than an 8-foot stop. 8 foot is therefore the normal pitch, and the others are added to it to make a larger, brighter sound. 16 foot stops are normal in pedal parts.

Mutation stops are stops in which a note does not sound a whole number of octaves above the normal pitch. Examples are the Tierce 1 3/5 (which sounds 2 octaves and a third above) and the Nazard or Twelfth 2 2/3 (one octave and a fifth).

Using the stops

An organist needs to learn which combinations of stops sound good together and how to balance them well. Each organ is different and has its own character.

The combination of stops that an organist chooses for a particular piece of music is called the "registration". The list of all the stops that a particular organ has is called the "specification". The specification of an organ shows the names of the stops for each of the manuals and for the pedals, as well as the list of couplers.

Organs also have buttons called "pistons" which help to change the registration in the middle of a piece. There are "toe pistons" operated by the feet, and "thumb pistons" which are placed just below each manual so that they can be pushed by the thumb while the fingers keep playing. Large organs often have "general pistons" which change any combination of stops across the organ. These are often be computerised so that players can set them up differently depending on the music they are going to play. If several players regularly use the instrument they can each have their own personal settings for the pistons which they can lock so that no one else can change them.

The pipes
Each stop controls a row of pipes, called a "rank". Each rank makes a different sound (one row for the "diapason" sound, another row for the "flute", another for the "trumpet" and so on). The stops control the air flow through the ranks. Some stops may control more than one rank. For instance, a Mixture stop of three ranks will have 182 pipes (3 ranks of 61 pipes each) and in some organs the Celeste is a 2 rank stop. The celeste pipes are tuned slightly sharper than the rest of the organ so that, when played together with another quiet stop such as the Salicional, there will be a pleasant throbbing beat because two pipes are slightly out of tune with one another. Organ Pipes are normally made of metal or wood. High quality metal organ pipes usually contain 75 percent tin or more, and the rest is lead. The Pipes are placed on windchests inside an "organ case" in a special room called an Organ chamber. A windchest is a box-like device which contains pallets that are opened and closed to admit air to a pipe so that it sounds. The pallets are operated by pull wires and rollers in the case of a tracker instrument but may also be operated by pneumatics or direct electric action using magnets.

There is always air being pumped into the windchest when the organ is switched on. In the days before electricity someone (an organ blower) had to pump the air into the windchest using bellows. This was hard work. Large organs would have needed more than one organ blower to do this job.

The history of the pipe organ

No other instrument has developed in such a wide variety of ways as the organ. If Bach, who lived in the early 18th century, had gone from his home in Germany to France, he would have found it impossible to play his music properly on French organs. If Couperin, who lived at the same time, had gone from his home in France to Germany, he would not have been able to play his music on the organs that Bach was using. Neither of them could possibly have played on an organ in England at the time. For one thing, English organs in the 18th century still had no pedals. This means that organists need to know a lot about what organs were like in other countries in other centuries in order to know what registrations to use when playing music by composers of the past.

The earliest organs

The earliest organs were water organs invented in Ancient Greece. The Romans used them in circuses and gladiator combats because they were loud. They were still popular in some countries a few hundred years ago, for example, in pleasure gardens.

The organ in the Middle Ages

In the Middle Ages large organs were built in the huge Gothic cathedrals in Britain. These instruments did not have different stops: all the ranks sounded at once. They were played by a slider mechanism. Only in the 11th, 12th and 13th centuries did they start to use a keyboard. The so-called Mixture Organ (or Blockwerk) still sounded several pitches at once. Very small organs called portatives (because they could be carried) were used in processions. Positives were a bit bigger and were used to accompany singing in the church. The Regal was like a portative but it had reeds and no pipes. It could be put on a table. The world's oldest organ is generally agreed to be the one built at Sion, Switzerland in the 15th century. the organ.

The organ in the Renaissance (about 1450-1600)
By about 1450, the organs that were being built in Germany and the Netherlands had two or three manuals and pedals. There were stops so that the player could choose which ranks he wanted to sound. The collection of pieces called the Buxheimer Orgelbuch (about 1470), is one of the first collections we have of organ music. French organs, too, were developing. In England, organs were quite small. Composers like John Bull, William Byrd and Orlando Gibbons wrote music for chamber organs. In the Netherlands Jan Pieterszoon Sweelinck was a very famous organist and teacher.

The organ in the Baroque period (about 1600-1750)
The Baroque period was a great period for organ music in Germany. Organs there were built on the Werkprinzip (literally: work principle) which meant that each keyboard with its pipes was built separately, like two or three different organs, although they were played from the same console. Organs like these were built by the famous Arp Schnitger (1648-1719). Many famous German composers wrote organ music, especially Johann Pachelbel (1653-1709) in South Germany and (Dietrich Buxtehude) (1637-1707) in North Germany. The great composer Johann Sebastian Bach (1685-1750) learnt from these composers and wrote some of the most famous organ music of all times. The great organ builder Gottfried Silbermann (1683-1753) lived during this time and built organs with a very beautiful tone. Instead of a keyboard called a Choir (or Chair Organ) he built an Oberwerk which was above the Hauptwerk (Great).

French organ builders at this time were very interested in colour (meaning: different sounds). Many stops had names like Cornet, Tierce and Prestant. When all the stops of the Principal chorus played together it was called the Plein jeux. This was like the medieval Blockwerk. All the reed chorus together was called Grand jeux. This would have sounded very loud and was used for dialogues and fugues. Composers included Nicolas de Grigny (1672-1703), Louis Marchand (1669-1732), Louis Nicolas Clérambault (1676-1749), Louis Claude Daquin (1694-1772) and François Couperin (1683-1733).

In England there was not much interest in developing the organ. It was used for accompanying the choir. There were no pedals. Pieces for organ were called voluntaries. Henry Purcell wrote a few organ pieces.

The organ in the Classical period: about 1750-1840
Organ composition reached a great peak in the work of J.S.Bach, but then people started to lose interest. Not many developments took place in organ-building during the Classical music period. Although Mozart played the organ and called it the "King of Instruments" he did not often write music for it. Among the organ builders at this time were Joseph and Claude-Ignace Callinet who built the organ at Notre-Dame's (St. Etienne, Loire) in 1837.

The organ in the Romantic period
The organ in 19th century Germany started to be used for imitating the sound of an orchestra. People also started to be interested in playing the music of J.S. Bach. Many Classical organs were re-built and sometimes they lost their original character. Organs in different countries started to sound the same.

Gradually, composers started writing for the organ again. Felix Mendelssohn (1809-1847) wrote some excellent sonatas and preludes and fugues which were inspired by Bach's music and made other composers want to write organ music. Robert Schumann (1810-1856) and Franz Liszt (1811-1886) wrote for the organ and later in the century Max Reger (1873-1916) and Sigfrid Karg-Elert (1877-1933).

In France, the organ builder Aristide Cavaillé-Coll (1811-1899) was a real genius. His organs had lots of new ideas including the Barker lever (which made it easier to play on coupled manuals) and placing families of stops on to separate chests. Organists could change their registrations quickly, pushing in or pulling out the stops that they needed. Composers included César Franck (1822-1890), Charles-Marie Widor (1845-1937) and Louis Vierne (1870-1937). The last two wrote long works in several movements which they called Symphonies because they were full of colourful sounds like those in a symphony orchestra. There were usually three manuals called Grand, Positif and Récit placed in that order (with Grand nearest to the player). The Grand had warm foundation stops and big reeds (it was like combining the classical plein jeux and grand jeux). The Positif had string stops as well as a solo reed, and the Récit had lighter reeds.

In England, Samuel Wesley (1766-1837) wrote some important organ music inspired by J.S. Bach, and his son Samuel Sebastian Wesley (1810-1876) was influenced by Continental Romantic composers such as Mendelssohn. In 1851, the organ builder Henry Willis built a large organ for Crystal Palace Exhibition. It had three manuals and a pedal board. This set the standard in English organ building for the future.

The organ in the Twentieth century

During the 20th century organ builders became more and more interested in returning to some of the ideas of the Baroque and Classical periods. Many organs now have electric action, but a good mechanical action has the advantage that the player feels more close to the instrument that he is playing. Some large 20th century organs are able to play many kinds of organ music. Other 20th century organs were built as copies of Baroque or Classical instruments, but this means these instruments are mainly suitable for Baroque or Classical music, and are not well suited for music of the 19th and 20th centuries.

In the 19th century, many organs in England and America were placed in corners of churches where they could not be heard very well. In the 20th century, organ builders thought more about the best position for the organ, so that the sound would fill the main part of the church, the nave.
Among the most famous 20th century organ composers are Marcel Dupré (1886-1971), Jehan Alain (1911-1940) and Olivier Messiaen (1908-1992) in France, Paul Hindemith (1895-1963) in Germany, and Edward Elgar (1857-1934) and Herbert Howells (1892-1983) in England. The Czech composer Petr Eben (1929-2007) was one of the most important organ composers at the end of the 20th century, writing in an individual style.

The organ as an accompanying instrument
As well as the obvious use of the organ for accompanying church choirs and congregational singing the organ has often been used to accompany instruments. In the Baroque period small organs were used to accompany solo instruments or small groups of instruments or orchestras. This kind of accompaniment was called continuo. Occasionally composers have written organ concertos in which the organ is the solo instrument and the orchestra accompanies. Handel wrote several of these. In modern times Francis Poulenc wrote an organ concerto. There is an important organ solo in Symphony no 3 by Saint-Saëns. Other orchestral works sometimes have organ parts. Organists have often made organ "transcriptions", i.e. arranged music written for other instruments so that it can be played on the organ.

Related pages
 Electronic organ
 Water organ
 Organ (music)
 Organ tablature

Footnotes

References
 "Organ" by Arthur Wills, London 1984 ()

Other websites
 Pipedreams Listen to pipe organ music, organ pictures and other information
 Sacred Classics  Online radio program of pipe organ and choral music
 The Pipe Organ
 Organlive.com Listen to streaming pipe organ music from a library of more than 7700 tracks.

Keyboard instruments
Former good articles

Pipe organ


The Teatro alla Scala, usually known as La Scala, is one of the most famous opera houses in the world. It is in Milan, Italy, which is the country where opera started at the beginning of the 17th century. The theatre opened on 3 August 1778. At first it was called Nuovo Regio Ducal Teatro alla Scala. The first opera to be performed there was Salieri's Europa riconosciuta.

Building of the theatre
There had been a theatre there before, called Teatro Ducale, but it had been destroyed by fire in 1776. The new theatre was built where there had been a church called Santa Maria della Scala. This is how the theatre got its name.

The theatre had more than 3,000 seats arranged in six tiers (six storeys) of boxes, and above that the two 'loggione' or galleries. It has a very large stage. The money for the building was found by selling the 'palchi' (boxes) to wealthy noblemen and other rich people in Milan. In the 'platea' (the main floor) there were no seats and the audience there stood up to watch, like they do today in the Royal Albert Hall at the Proms. The orchestra could be seen very well as they were not in an orchestra pit like they are today.

Above the boxes, La Scala has always had a gallery where people who are not so rich can watch. This is still there today. It is called the loggione. Some people in the loggione, known as the Claque, are known to applaud wildly if they like a singer, or boo loudly if they do not like a singer. During La Scala's history this has often been because of bribery or blackmail.

La Scala was originally lit with 84 oil lamps mounted on the palcoscenico (ceiling) and another thousand in the rest of theater. In case they ever caught fire, several rooms were filled with hundreds of water buckets. Later, oil lamps were replaced by gas lamps. In 1883 electric lights were put in.

The building was renovated in 1907. After that it had 2,800 seats as it does today. In 1943, during World War II, La Scala was badly damaged by bombing. It was rebuilt and reopened on 11 May 1946, with a brilliant concert conducted by Arturo Toscanini, with a soprano solo by Renata Tebaldi.

Verdi
Many famous operas were first performed at La Scala, including some by Giuseppe Verdi. For several years, however, Verdi did not allow his music to be played here because he did not like the way the orchestra had played it. However the composer later conducted his Requiem there on May 25, 1874, and in 1886 announced that La Scala would host the premiere of his opera Otello. The first performance of his last opera, Falstaff was also given in this theatre.

Today

La Scala's season traditionally opens on 7 December, Saint Ambrose's Day, Milan's patron saint. All performances must end before midnight; long operas start earlier in the evening if necessary.

There is also a La Scala Museum (Museo Teatrale alla Scala) which has an extraordinary collection of paintings, drafts, statues, costumes, and other documents about opera and La Scala's history.

Recently there have been more renovations to La Scala. Some people were worried that it would spoil the historic building, but the opera company were very pleased when the work was done. There was a new stage and lots more room behind the stage. The heavy red carpets were taken away and the sound was better. The seats include monitors so that the audience can follow the words in English or Italian if it is in a foreign language (not Italian).
The renovated opera house was opened on 7 December 2004 with the same opera by Salieri that had opened it in 1778. The conductor was Riccardo Muti.

References

Other websites
 La Scala official website

Scala, La
Buildings and structures in Milan
1778 establishments
18th-century establishments in Italy
1770s establishments in Europe

La Scala


A ladder is a tool which is made for people to climb up or down. Ladders have two vertical supports that go along the whole length of the ladder. Between these supports are the horizontal rungs. The rung is what the climber can put his foot on. The climber can use his hands to hold on to the rungs above him, or to the supports at the side.

Some ladders are made in one piece. They can be carried around and made to lean against something such as the wall of a house. There should be a good distance between the bottom of the ladder and the wall so that the ladder is not too vertical, otherwise the ladder might fall backwards and the climber would fall off. Sometimes these ladders are extension ladders. Extension ladders are made in two or more sections so that the ladder can fold up to make it easier to carry about and to store. To open up the ladder, each section slides up almost to the top of the next section.

Step ladders are useful in the home or the garden to reach things that are not too high, e.g. ceilings or the tops of hedges. They have two parts which are joined by a hinge, so that they are shaped like an upside down V. There is usually a platform at the top to stand on, but this can be dangerous unless great care is taken that the ladder will not wobble or fall down.

Some ladders are vertical (they go straight up or down). These are fixed onto something. Examples are: ladders in a swimming pool for climbing in and out of the water, small ladders to climb up to a top bunk bed, ladders at the side of a big boat or at the side of a canal lock or of any other high or low construction where workmen may need to get up or down to do repairs.

Fire engines always have ladders. They often have a turntable ladder which makes it possible for the ladder to be facing in any direction.

Rope ladders can be folded away easily. They may be used for climbing trees or for rock climbing or in caves.

References

Tools
Construction

Ladder


Balboa Park is a  historic urban cultural park in San Diego, California, United States. In addition to open space areas, natural vegetation zones, green belts, gardens, and walking paths, it contains museums, several theaters, and the San Diego Zoo. There are also many recreational facilities and several gift shops and restaurants within the boundaries of the park. Placed in reserve in 1835, the park's site is one of the oldest in the United States dedicated to public recreational use. Balboa Park is managed and maintained by the Parks and Recreation Department of the City of San Diego.

Balboa Park hosted the 1915–16 Panama–California Exposition and 1935–36 California Pacific International Exposition, both of which left architectural landmarks. The park and its historic Exposition buildings were declared a National Historic Landmark and National Historic Landmark District in 1977, and placed on the National Register of Historic Places.

Park attractions
Balboa Park contains museums, gardens, attractions, and venues.

Museums

Centro Cultural de la Raza
Comic-Con Museum
George W. Marston House
Mingei International Museum
Museum of Photographic Arts
Museum of Us (formerly the Museum of Man)
Reuben H. Fleet Science Center
San Diego Air & Space Museum
San Diego Art Institute
San Diego Automotive Museum
San Diego History Center
San Diego Model Railroad Museum
San Diego Museum of Art
San Diego Natural History Museum
Timken Museum of Art
Veterans Museum and Memorial Center

Gardens

1935 (Old) Cactus Garden
Alcazar Garden
Australian Garden
Botanical Building
California Native Plant Garden
Casa del Rey Moro Garden
Desert Garden
Florida Canyon Native Plant Preserve
Marston House Garden
George Washington Carver Children's Ethnobotany Garden
Inez Grant Parker Memorial Rose Garden
Japanese Friendship Garden
Lily Pond
Palm Canyon
Trees for Health Garden
Veterans Memorial Garden
Zoro Garden

Attractions and venues

 Balboa Park Activity Center
 Balboa Park Carousel, built in 2010 and located in Balboa Park since 1922. It was originally in the location where the Fleet Science Center is now, and was moved to its current spot near the Zoo entrance in 1968. It retains most of its 100-year-old original equipment: 52 hand-carved wooden animals and four chariots, a 10-horsepower General Electric motor, same music, same oil paintings.
 Balboa Park Club
 Balboa Park Lawn Bowling Greens
 Rube Powell Archery Range
 Balboa Stadium
 Casa de Balboa
 Casa del Prado
home of San Diego Youth Symphony and the San Diego Junior Theatre
 Electriquettes (1915 electric-powered wicker carts)
 House of Pacific Relations International Cottages
 Morley Field Sports Complex
 Balboa Park Golf Course
 Bud Kearns Memorial Swimming Pool
 Morley Field Archery Range
 Morley Field Ballpark & baseball/softball complex
 Morley Field Bocce Ball Courts
 Morley Field Cross Country Course
 Morley Field Disc Golf Course
 Morley Field Dog Park
 Morley Field Petanqueodrome
 Morley Field Remote Control Race Car Track
 Morley Field Tennis Stadium & Balboa Tennis Club complex
 San Diego Velodrome
 Municipal Gymnasium
 Old Globe Theatre
 Palisades Building
home of Recital Hall and the Marie Hitchcock Puppet Theater
 San Diego Zoo
 the Zoo operates the Balboa Park Miniature Train ( gauge)
 Spanish Village Art Center
 home of the San Diego Mineral and Gem Society
 Spreckels Organ Pavilion
 Starlight Bowl
 War Memorial Building
 WorldBeat Cultural Center

Geography

The park is essentially rectangular, bounded by Sixth Avenue to the west, Upas Street to the north, 28th Street to the east, and Russ Boulevard to the south. The rectangle has been modified by the addition of the Marston Hills natural area in the northwest corner of the park, while the southwest corner of the rectangle is occupied by a portion of the Cortez Hill neighborhood of Downtown San Diego and San Diego High School, both of which are separated from the park by Interstate 5. Also encroaching on the northern perimeter of the park is Roosevelt Middle School.

Two north-south canyons—Cabrillo Canyon and Florida Canyon—traverse the park and separate it into three mesas. The Sixth Avenue Mesa is a narrow strip bordering Sixth Avenue on the western edge of the park, which provides areas of passive recreation, grassy spaces, and tree groves, and a camp for Camp Fire. The Central Mesa is home to much of the park's cultural facilities, and includes scout camps, the San Diego Zoo, the Prado, and Inspiration Point. East Mesa is home to Morley Field and many of the active recreation facilities in the park.

The park is crossed by several freeways, which take up a total of  once designated for parkland. In 1948, State Route 163 was built through Cabrillo Canyon and under the Cabrillo Bridge. This stretch of road, initially named the Cabrillo Freeway, has been called one of America's most beautiful parkways. A portion of Interstate 5 was built in the park in the 1950s.

Surrounding the park are many of San Diego's older neighborhoods, including Downtown, Bankers Hill, North Park, and Golden Hill.

Park layout

Balboa Park is a primary attraction in San Diego and the region. Its many mature, and sometimes rare, trees and groves comprise an urban forest. Many of the original trees were planted by the renowned American landscape architect, botanist, plantswoman, and gardener Kate Sessions. An early proponent of drought tolerant and California native plants in garden design, Sessions established a nursery to propagate and grow for the park and the public.

The park's gardens include Alcazar Garden, Botanical Building, Desert Cactus Garden, Casa del Rey Moro Garden, Inez Grant Parker Memorial Rose Garden, Japanese Friendship Garden, Bird Park, George W. Marston House and Gardens, Palm Canyon, and Zoro Garden.

The main entrance to the park is via the Cabrillo Bridge and through the California Quadrangle. That entry is currently a two-lane road providing vehicle access to the park. A plan to divert vehicle traffic around to the south of the California Quadrangle, so as to restore it as a pedestrian-only promenade, was dropped after legal challenges, but was reapproved after the legal challenges failed and was scheduled for completion in 2019.

El Prado, a long, wide promenade and boulevard, runs through the park's center. Most of the buildings lining this street are in the Spanish Colonial Revival architecture style, a richly ornamented mixture of European Spanish architecture and the Spanish Colonial architecture of New Spain-Mexico. Along this boulevard are many of the park's museums and cultural attractions, including the Museum of Us, the San Diego Museum of Art, the Museum of Photographic Arts, the San Diego Art Institute, the San Diego Model Railroad Museum, the San Diego Natural History Museum, the San Diego History Center, the Reuben H. Fleet Science Center, and the Timken Museum of Art. Other features along El Prado include the Reflection Pond, the latticed Botanical Building, and the Bea Evenson Fountain. Next to the promenade are the San Diego Air & Space Museum and the San Diego Automotive Museum.

Theatrical and musical venues include the Spreckels Organ Pavilion, featuring one of the world's largest outdoor pipe organs; the Old Globe Theatre complex, which includes a replica of Shakespeare's Globe Theatre as well as an outdoor stage and a theatre in the round; and the Starlight Bowl – an outdoor amphitheatre. The Casa Del Prado Theater is the home of San Diego Junior Theatre, the country's oldest children's theatre program. The House of Pacific Relations International Cottages collected on El Prado offer free entertainment shows.

The Botanical Building, designed by Carleton Winslow, was the largest wood lath structure in the world when it was built in 1915 for the Panama-California Exposition. It contains large specimen palms and other plants and sits next to a long reflecting pool on the El Prado side.

Located in the eastern third of the park is the Morley Field Sports Complex, which includes the Balboa Park Golf Complex, which contains a public 18-hole golf course and 9-hole executive course; the San Diego Velodrome; baseball and softball fields; cross country running course; the USTA-honored Balboa Tennis Club and tennis courts; archery ranges; the Bud Kearn public swimming pool; and a disc golf course.

Among the institutions and facilities within the park's borders but not administered by the city's Parks Department are the San Diego Zoo, the Naval Medical Center San Diego (NMCSD), and San Diego High School. Other attractions in various areas of the park include chess and bridge outdoor tables, horseshoe pits, playgrounds, walking and jogging trails, sports fields and courts, and picnic areas. Clubs and facilities for pétanque and lawn bowling are based in the park. There is also Spanish Art Village which consists of art shops.

History

Kumeyaay village and native Californian/Bajeño neighborhood
Prior to the establishment of the park, the area was home to a Kumeyaay village informally known as Hatam's Village (or Hata'am) in Florida Canyon just south of what is now the Naval Medical Center. Its existence survived the 1852 effort to remove Kumeyaay villages within half a mile of the city. The village was kept active under Jośe Manuel Polton, also known as Hatam, who transformed the village into an urban Native American neighborhood for urbanized Native Californians and Baja Californians in San Diego seeking jobs. The neighborhood lasted into the 1890s through the advocacy of Hatam and his successor Juan Gonzales before it was dismantled and became Balboa Park.

Land reserved

Spain and later Mexico made a practice of setting aside large tracts of land for the common use of citizens. In 1835, the Alta California authorities set aside a  tract of pueblo land in San Diego to be used for the public's recreational purposes. This land included the site of present-day Balboa Park, making it one of the oldest places in the United States dedicated to public recreational usage.

No further activity took place until 1845, when a survey was done by Henry D. Fitch to map the 47,000 acres. Three years later, the Mexican government was forced by the Mexican–American War to cede Alta California, including San Diego, to the United States.

On February 15, 1868, the city's Board of Trustees was asked to create a public park out of two  plots of land just northeast of the growing urban center of "New Town"—present-day Downtown San Diego. The request was made by one of the Trustees, E. W. Morse, who had picked the site in coordination with real estate developer Alonzo Horton. There is a sculptural group of Horton, Marston, and Morse  by Ruth Hayward in the park.

Park establishment

Subsequently, a resolution to set aside for a large city park not just two plots of land, but nine plots totaling , was approved by the city's Board of Trustees on May 26, 1868. Then in 1870, a new law called the "Act to Insure the Permanency of the Park Reservation", was passed by the state legislature, which said, "These lands (lots by number) are to be held in trust forever by the municipal authorities of said city for the purpose of a park".

It was around this time that San Diego residents were developing fondness for the park, as illustrated by their insistence on keeping the park intact when in 1871 there was an attempt to overturn the state law so as to allow for private purchase of some of the park land. At the urging of would-be land speculators and the city attorney, State Senator James McCoy quietly introduced a bill in the California state legislature to repeal the 1870 law. A San Diego resident learned of the plan and informed higher powers at the state level in Sacramento, California.  The conspiracy was leaked to the press, exposing the city officials involved. A public safety committee formed and collected signatures supporting the current existence of the park. Their plea was successful and the bill was killed in the legislature. San Diego was the second city in the U.S. to dedicate a large park after New York City's 1858 establishment of Central Park.

A City Park: 1872–1909

For the first few decades of its existence, "City Park" remained mostly open space. The land, lacking trees and covered in native wildflowers, was home to bobcats, rattlesnakes, coyotes, and other wildlife. Numerous proposals, some altruistic, some profit-driven, were brought forward for the development and use of the land during this time, but no comprehensive plan for development was adopted until 1902.

Nevertheless, some buildings were constructed, including an orphanage and women's shelter (later burned down), a high school (Russ High School – later San Diego High School), and several gardens maintained by various private groups.  One of the most celebrated of these early usages was a 36-acre nursery owned and maintained by local horticulturist and botanist Kate Sessions, who is often referred to as "the mother of Balboa Park." Although owned by Sessions, by agreement with the city the nursery was open to the public, and Sessions donated trees and plants to the city every year for its beautification.  Sessions is responsible for bringing in many of the different varieties of native and exotic plants in the park.  Her work was so progressive that she was in fact the first woman awarded the Meyer Medal for "foreign plant importation" by the American Genetic Association.

Other developments from this time include two reservoirs, an animal pound in Pound Canyon (later renamed Cabrillo Canyon), and a gunpowder magazine in the area now known as Florida Canyon. The earliest recreational developments in the park were in the "Golden Hill Park" area off 25th street. The National Register listed the rustic stone fountain designed by architect Henry Lord Gay as the oldest surviving designed feature in the park.  Other attractions in the area included a children's park, walking trails, and a redwood bird aviary.

Indigenous Californians and Bajenos began to flock to the Kumeyaay village in Florida Canyon looking for work in San Diego during this period. A Native Californian urban exclave was built up in the canyon, which lasted up until the 1900s when the neighborhood was torn down in preparation for the Panama–California Exposition.

Preparation for the 1915 Expo: 1910–1914

Source:

Preparations for the 1915 Panama–California Exposition created much of the park's present-day look-and-feel and designed amenities.

Beginning in 1909, San Diego Chamber of Commerce president G. Aubrey Davidson suggested that the park hold an expo to coincide with the 1915 opening of the Panama Canal. Davidson believed an expo would help improve commerce (it would advertise that San Diego was the first U.S. port of call vessels encountered after passing through the canal and sailing north), build the city's population, and expand the infrastructure of the park. He later explained the significance of holding the expo in San Diego:

After a 1910 contest to rename City Park, the park was named after Vasco Núñez de Balboa, the first European to cross Central America and see the Pacific Ocean.

San Diego would be the smallest city to ever hold a World's Fair; its population at the time was less than 40,000. The expo was organized by a group of San Diego business leaders, including Ulysses S. Grant Jr., and was funded at an initial cost of $5 million (including $1 million from voter-approved bonds for landscaping). Developer and civic leader D. C. Collier was chosen as General Director of the expo; he made major decisions such as locating the expo on the park's central mesa, using California Mission Revival Style architecture for the buildings, and featuring "human progress" as the theme. A similar fair, the 1915 Panama–Pacific International Exposition, was also planned in "far to the north" San Francisco to celebrate the canal opening. Although $5 million had been set aside by Congress for celebrations of the Panama Canal opening, the majority of the funds went to the San Francisco expo.

In anticipation of the exposition, many of San Diego's business and city leaders began to develop separate plans for the park. John D. Spreckels, owner of the San Diego Electric Railway, wanted to shift the location of the main public plaza to add room for exhibitors — and to allow his streetcar system to traverse the park and extend to the North Park and University Heights neighborhoods.

The Exposition's lead designer and site planner was architect Bertram Goodhue, well known for his Gothic Revival Style churches in New York and Boston, who sought a regionally appropriate aesthetic to use in Southern California. Goodhue and associate architect Carleton Winslow chose to use the styles of highly ornamented Spanish Baroque architecture with the Spanish Colonial architecture created during the Spanish colonization era in New Spain-Mexico and the lower Americas, with Churrigueresque and Plateresque detailing "updating" the already popular Mission Revival Style—to create the Spanish Colonial Revival Style.

The buildings and the style were extremely well received by the public and design professionals in California and nationally, becoming a reigning style for decades, and still the primary vernacular style in much of California.  Goodhue's associate architect was Carleton M. Winslow, who is solely credited with the lattice-work Botanical Building and other structures.  Goodhue's team, which included Kate Sessions and Lloyd Wright for landscape design, had won out over the local and more modernist Irving Gill to get the commission. One of the most significant improvements to the park from that time was the construction of the Cabrillo Bridge across a major canyon in the city. The bridge connects the main portion of the park with the western portion and with Laurel Street.

A lavish groundbreaking ceremony for the fair's construction was held in July 1911.

The Panama-California Exposition: 1915–1916

On December 31, 1914, the Panama-California Exposition opened, with Balboa Park "crammed full" of spectators. President Woodrow Wilson pushed a telegraph button in Washington, D.C., to symbolically open the ceremonies by turning on the power at the park. Yellow and red were the themed colors of the event and were displayed throughout. All of the employees, workers, security people, and management staff were dressed in period Spanish and Mexican military uniforms, and much of the park was filled with plantings of exotic plants.  Over 40,000 red Poinsettia plants, all in full bloom, were used.  The event attracted the national attention organizers had sought.  Even Pennsylvania's Liberty Bell made a brief three-day appearance in November 1915. The event was such a success the fair was extended through 1916.  Over the two years, it drew more than 3.7 million visitors, including Henry Ford, William Jennings Bryan, Thomas Edison, Theodore Roosevelt, and William Howard Taft. The expo actually turned a slight profit, which was donated to the San Diego Museum in the park.

Roosevelt, approving of the buildings' architecture, recommended that the "buildings of rare phenomenal taste and beauty" be left as permanent additions. The majority of the buildings were only supposed to remain standing through 1916 and were not constructed with long-lasting materials. When the expo ended, several city discussions were held to determine what to do with the buildings. Goodhue recommended demolishing the buildings, saying "They are now crumbling, disintegrating and altogether unlovely structures, structures that lack any of the venerability of age and present only its pathos, and the space they occupy could readily be made into one of the most beautiful public gardens in the New World." Joseph W. Sefton Jr., president of the Society of Natural History, also called for their demolition, citing fire hazards: "All those old exposition buildings are nothing but fire traps. ... They are pretty to look at, but we may wake up any morning and find them gone, and our million dollars['] worth of exhibits with them." However, a city-appointed committee hired an architect to review the buildings, and he determined that they could be restored by a slight margin over any costs to demolish the buildings. The necessary funds and materials for restoration were donated by San Diegans and the labor was financed by the federal government. Some of the buildings and infrastructure constructed for the Panama-California Exposition that still exist include:
Cabrillo Bridge (completed April 12, 1914)
California State Building and Quadrangle (completed October 2, 1914 – now the Museum of Us)
Administration Building (completed March 1912 – now: offices of the Museum of Us)
Botanical Building
California Bell Tower (completed 1914)
New Mexico Building (now: Balboa Park Club)
Spreckels Organ Pavilion (dedicated December 31, 1914)

California Pacific International Exposition: 1935–1936

Balboa Park's second big event, the California Pacific International Exposition, came in 1935. This Exposition was intended to promote the city and remedy San Diego's Great Depression ills. Balboa Park was reconfigured by San Diego architect Richard S. Requa, who also oversaw the design and construction of many new buildings, some to be permanent. Facilities added at that time and still in use include the Old Globe Theatre, the International Cottages, and the Spanish Village.

The 1935 Exposition left behind colorful stories of its exhibits and entertainments. The Gold Gulch was a forerunner of the many "frontier town" themed areas of later amusement parks. The controversial Zoro Garden Nudist Colony,  "Midget Village", and sideshow entertainments including fan dancer Sally Rand added to the lore. The Exposition also provided visitors with early glimpses of 'Alpha', a walking silver robot; and a strange new electrical device called a "television".

Like the first exposition, the 1935 Fair was so successful it was extended for a second year. Opening ceremonies for the second season began when President Franklin D. Roosevelt pressed a gold telegraph key in the White House to turn on the exposition's lights. He later visited the exposition; other notable guests included Herbert Hoover, Mae West, and Jack Dempsey. Funded at $20 million, the 1935–1936 event counted 6.7 million visitors—almost double the total of the 1915–16 exposition.

At the conclusion of the expo, San Diegans voted again on what to do with the park and its buildings. Banker Joseph Sefton Jr. called for the buildings' removal, "They are hideous and badly placed. Had we torn out the 1915 exposition buildings and landscaped the park we would have a beautiful place there now and not a long row of ramshackle firetraps." Several proposals were developed for converting buildings to museums and several groups attempted to have some of the park land sold to finance other projects.

World wars

During both the Great War and World War II, the park was handed over to the Department of the Navy to be used as a barracks and training ground and was an extension of Naval Medical Center San Diego. By 1917, after $30,000 in repairs and modifications were made to the original buildings, over 5,000 U.S. troops were using the park for training.

Coinciding with the Panama–California Exposition, the Commandant of the Marine Corps instructed 2nd Battalion of the newly established 4th Marines to represent the Marine Corps at the event. On December 19, 1914, Marine Barracks, Balboa Park, was established as the second, and during its period, and only Marine base in San Diego. It was established by Marines under the command of Colonel Pendleton. It remained in place until 1921, when a more permanent base was established in Dutch Flats, itself a predecessor of Marine Corps Recruit Depot, San Diego. Under the conditions of usage, upon closing, the Marine Corps returned the buildings they had used in the exact condition that they had received them. Although some buildings were scheduled to be demolished due to disrepair, several San Diego groups organized to ensure the buildings were kept.  Donated funds allowed for improvements to the buildings' integrity and interiors.

During World War II, the park was renamed Camp Kidd, after Rear Admiral Isaac Kidd. Buildings within the park were used for multiple purposes, including hospital wards, training facilities, and barracks. After the attack on Pearl Harbor, many of the wounded were transported to Camp Kidd's hospital wards. Camp Kidd also served as a Reception Center for sailors until 1944, when those activities were transferred to Camp Elliott; this allowed for additional hospital expansion. It was returned to civilian authority in 1946, and repair costs to return the buildings and infrastructure to their pre-war status totaled $840,000, with the majority reimbursed by the Navy. In 1948, the funds were used to restore seven buildings that were deemed unsafe.

Post-war 20th century

A new addition to the park during the post-war 1940s was the carillon in the California Tower (1946), which chimes the time every quarter-hour. The San Diego Junior Theater, a program of the Old Globe Theatre, was established in 1948, performing in the Prado Theatre. The amphitheater formerly known as the Ford Bowl became the Starlight Bowl, home of the Starlight Musical Theater (also known as the San Diego Civic Light Opera and as Starlight Opera), which performed Broadway musicals outdoors in the summer.

In 1959, the city hired an architectural firm to map out a plan for the park based on the suggestions of San Diegans along with the firm's recommendations. The initial review called for 13 of the original 1915 buildings to remain while replacing 11 others with new buildings in their place. The plan also called for adjusted roadways, additional landscaping, and improvements in parking. By 1967, the city and private charities such as the Committee of 100 undertook a major effort to restore the park's historic buildings. Most of the original Exposition buildings were continuing to deteriorate with some lacking foundations and minimal structural support. By the 1990s some of the Prado buildings were deteriorating so badly that "pieces of plaster regularly fell off the walls." Several crumbling buildings were torn down and replaced with permanent structures which were carefully detailed to maintain the original appearance. The Science and Education Building and the Home Economy Building were demolished to make room for the expansion of two new wings for the Timken Museum of Art. The loss of these two buildings along with the Casa de Balboa, the House of Charm, and the House of Hospitality, resulted in the formation of the independent organization, Committee of One Hundred, to attempt to preserve the exhibition buildings.

Several new museums opened during the 1960s and 1970s: the Timken Museum of Art in 1965, the Centro Cultural de la Raza in 1970, and the Reuben H. Fleet Science Center in 1973. The 1915–1916 exposition's Food and Beverage Building was rebuilt and reopened in 1971 as Casa del Prado.

Balboa Park, and the historic Exposition buildings, were declared a National Historic Landmark and National Historic Landmark District in 1977, and placed on the National Register of Historic Places. The following year two historic park structures burned down in two separate arson fires: the Aerospace Museum in the former Electric Building, and the 1935 Old Globe Theatre. The Aerospace Museum (now the San Diego Air and Space Museum) lost over $4 million in exhibits, and was reopened after moving into the old Ford Building. The Old Globe Theatre produced its 1978 season on a temporary outdoor stage, which was later upgraded to become one of the Globe's three theaters. The Old Globe Theatre itself was rebuilt and reopened in 1981. Queen Elizabeth II presented at the dedication ceremony for the theatre in 1983.

Throughout the 1980s, there were multiple reports throughout Balboa Park of vandalism, murder, rape, arson, and minor petty crimes. The resulting negative publicity during this period inspired Bruce Springsteen to write a song entitled "Balboa Park" focusing on the unpleasant aspects of the park. One of the Old Globe Theatre's starring actors was stabbed to death in the middle of the day in February 1985. A 36-year-old woman was gang-raped and murdered in the park in June 1986. To counter the increase in crime, city officials expanded police patrols in the park, and many of the individual museums hired security guards. After two murders in 1993 and the shooting of a young drama student walking across the Cabrillo Bridge in 1994, nighttime lighting in the park was increased, and video cameras were installed in several locations to allow park rangers and police to better monitor the area.

In 1998, the Reuben H. Fleet Science Center opened a larger building at its present location. The following year, the Hall of Champions Sports Museum moved to the old Federal Building.

21st century

By 2001, over 12 million people visited the park each year.

The Balboa Park Conservancy, a non-profit group to preserve and promote the park, was proposed in 2009 and was officially launched on September 14, 2010.

On the night between August 11 and 12, 2012, the 100-year-old Lily Pond at Balboa Park was vandalized overnight. Officials said the water level in the pond was reduced to 2 inches and a pipe was broken. No fish or turtles were killed, but damage to the pond and surrounding landscaping was estimated at several thousand dollars. There had been reports of a "midnight water gun fight" planned for that night, and a video of such an event was later uploaded to YouTube. In early 2013, work began on repairing the Lily Pond, including removing the fish and plants to temporary homes, draining the pond, and repairing the concrete lining. In addition, plumbing repairs were completed, and 27 new plant platforms were constructed to hold the lilies in place. After the reservoir was filled with water and the fish were re-introduced, the Lily Pond opened once again to the public in late February, 2013.

In 2017, the State of California designated Balboa Park as a cultural district, given its central role in the culture of San Diego.

Centennial
As the centennial of the 1915 exposition approached, there was talk of a grand year-long celebration "on the scale of the 1915 and 1935 fairs".  A nonprofit organization, Balboa Park Celebration Inc., was formed in 2011 to organize the festivities and "reintroduce Balboa Park to the world." However, fundraising faltered and plans failed to materialize. In March 2014 the nonprofit organization disbanded, turning over its records and responsibilities to the city less than a year before the celebrations were supposed to start. Mayor Kevin Faulconer and City Council President Todd Gloria, who had been major proponents of a large-scale celebration, expressed disappointment with the group's "lack of significant progress achieving its goals" and said they would work together to "move forward with a more practical and realistic celebration." A City Council committee ordered an audit of the organization's finances to find out what became of the $2.8 million in public funds allocated to it by the council.

The 2015 "Celebration" of the Centennial became a grassroots movement with all the Parks's institutions celebrating with special exhibits and events. On Dec. 31 Carol Williams, with special guests, ushered in the year with an evening of music at the Spreckels Organ Pavilion.  On Saturday, May 9, The Garden Party of the Century invited Garden enthusiasts from throughout the county to come enjoy the park. A floral wagon parade highlighted the event.

For the Centennial the Park's Department working together with Friends of Balboa Park created an Adopt-a-Plot program.  Throughout the park various volunteer organizations have adopted garden areas and have started a transformation to enhance the park's beauty for the next 100 years.

In 2016, the Electriquettes returned to Balboa Park.  They had been planned for the Centenniel celebration and several were on display in 1915, but it took until the Spring of 2016 for them to return to be driven on the Prado.  They are electric-powered wicker carts which can be rented and driven in the main Prado area of the park.

In 2017, it was announced that San Diego Comic-Con would be opening a museum in the park, displacing the San Diego Hall of Champions, which will move to Petco Park.

Traffic rerouting and parking changes
In August 2010 a proposal was unveiled by then-Mayor Jerry Sanders and philanthropist Irwin M. Jacobs to divert traffic away from the central Prado areas of the park, such as the Plaza de Panama in front of the Art Museum and the California Quadrangle in front of the Museum of Us, and restore the areas to pedestrian use. The plan would provide replacement parking via a two-level parking garage at the site of the current Spreckles Organ Pavilion parking lot. The plan also called for changes in access to the park via the Cabrillo Bridge. The bridge would become eastbound only so that people could enter the park via the Cabrillo Bridge but could exit only via Park Boulevard. Inbound traffic would be deflected via a new bridge offramp through the current Alcazar Gardens parking lot toward the new parking garage. The Alcazar Gardens parking lot would be for disabled parking only and for loading and unloading of passengers. The new parking garage would house 750–900 cars and would be landscaped on top. The plan became controversial because of its alteration to the appearance of the bridge and the possibility of charging for parking in the parking garage. In July 2012 the City Council voted to proceed with the Jacobs plan. Construction was due to begin in October 2012 and be completed in time for the park's centennial in 2015. However, the scheduled start of construction was pushed back to February 2013 due to a legal challenge from the Save Our Heritage Organisation (SOHO). In February 2013 a judge voided the project, after which Jacobs withdrew his offer to finance it. Since the Park's master plan already called for removing the 67-space parking lot from the Plaza de Panama, the city went ahead with that portion of the proposal removing all parking from the plaza and converting it into a pedestrian area with tree planters, seats, and tables.

Eventually the courts ruled against the challengers and in 2016 the City Council re-approved the project with its original cost estimate of $45 million now expanded to $79 million. The project will remove all traffic from the Plaza de Panama and the California Quadrangle, diverting it toward a 3-level underground parking garage with a rooftop garden and 797 paid parking spaces. All other parking in Balboa Park will remain free. The cost of the project will be divided between the city, which plans to use the parking lot as a revenue source, and private philanthropy. The proposed completion date is July 2019.

In December 2016, opponents of the traffic redirect and its associated 'bypass bridge' sued to stop it from moving forward on the grounds that it would fundamentally change the historic monument. City Attorney Mara Elliot called this an "unjustified attempt" to delay the project, but SOHO claimed it would have adverse effects on the park and its historic integrity.

Special events
Balboa Park frequently holds events throughout its museums, venues, and plazas. These events include free weekly concerts at the Spreckles Organ Pavilion each Sunday at 2:00 p.m., guest speakers, and annual parades, cultural festivals, and fairs. The festival "December Nights" (originally called "Christmas on the Prado") takes place in Balboa Park on the first full weekend in December each year. EarthFair, described as one of the largest free annual environmental fairs in the U.S., is held in the park every April. The event celebrates Earth Day, and includes a parade, musical performances, children's area, international food, exhibit booths and information on various topics related to the environment. In 2010, over 70,000 people attended the fair. The two-day San Diego Pride Festival is held in the Marston Point area of Balboa Park each July; the 2011 event was attended by more than 150,000 people. In 2016, WikiConference North America was held at the park. A cherry blossom festival is also celebrated annually in March in the Japanese Friendship Garden.

Each summer, free outdoor concerts are performed Monday through Thursday at the Spreckels Organ Pavilion. Free organ concerts are held each Sunday at 2:00 p.m., year round.

Several races and marathons include the park in the courses. The Foot Locker Cross Country Championships are held in Balboa Park annually. First started in 1979, the race is held in Morley Field. Marathons such as the San Diego Rock 'n' Roll Marathon and the America's Finest City Half Marathon, as well as the American Cancer Society "Making Strides Against Breast Cancer" walk, and the Susan G. Komen "Race for the Cure" and other annual events begin or end in Balboa Park.

FlixBus services the park with a stop on Presidents Way near Pan American Plaza.

Cultural references

 The 1915 silent film Fatty and Mabel at the San Diego Exposition takes place at the 1915 Exposition and stars Roscoe "Fatty" Arbuckle and Mabel Normand.
 Citizen Kane has scenes from Charles Kane's mansion "Xanadu" filmed at buildings in Balboa Park, with the San Diego Zoo standing in for Kane's private bestiary.
 Portions of the 1979 movie Scavenger Hunt were filmed in and around Balboa Park and the San Diego Zoo.
 MyNetworkTV's Desire filmed a 2006 episode scene in the Spreckels Organ Pavilion.
 The California Tower appears in the film Almost Famous.
 Scenes from The Samuel Project were filmed in Balboa Park.
 The video games Tony Hawk's Underground and Midnight Club 3: DUB Edition use Balboa Park for their San Diego levels.
 The internet series Mega64 often films their sketches at Balboa Park.
 Bruce Springsteen's album The Ghost of Tom Joad includes a song about Balboa Park.
 The cover photo of the Beach Boys' album Pet Sounds was taken at the San Diego Zoo's children's petting zoo.
 The 2003 movie National Lampoon Presents Dorm Daze'''s exterior shots of the "college campus" are from Balboa Park.
The 2nd copy of the iconic statue from the film Rocky III is featured in the San Diego Hall of Champions.
 The 1995 Chuck Norris film Top Dog was set in Balboa Park.
 Balboa Park is prominently featured as a setting for the 2007 naval thriller, Defiance'', by Don Brown.

See also

California native plants
Central San Diego
History of San Diego
List of parks in San Diego
Park Conservancy

References

Bibliography

External links

 Official San Diego Parks Department –  Balboa Park website
 Balboa Park Master Plan
 Balboa Park Foundation
 Balboa Park Cultural Partnership
 The Committee of One Hundred: dedicated to preserving Balboa Park's Spanish Colonial Architecture
 Friends of Balboa Park

1868 establishments in California
Historic districts in San Diego
Historic districts on the National Register of Historic Places in California
History of San Diego
Culture of San Diego
Landmarks in San Diego
Municipal parks in California
National Historic Landmarks in California
National Register of Historic Places in San Diego
Parks in San Diego
Parks on the National Register of Historic Places in California
Spanish Colonial Revival architecture in California
Spanish Revival architecture in California
Urban public parks
World's fair architecture in California
World's fair sites in California

Balboa Park (San Diego)


Judeo-Arabic languages are a collection of Arabic language dialects spoken by Jews living or formerly living in Arabic-speaking countries.  Just as with the rest of the Arab world, Arabic-speaking Jews had different dialects for the different regions where they lived.  Most Judæo-Arabic dialects were written in modified forms of the Hebrew alphabet, often including consonant dots from the Arabic alphabet to accommodate phonemes that did not exist in the Hebrew alphabet.

In retaliation for 1948 Arab-Israeli War, Jews in Arab countries became subject to increasingly insufferable discrimination and violence, causing virtually all of them to flee en masse to Israel.  Their dialects of Arabic did not thrive in Israel, and most became extinct, replaced by the Modern Hebrew language.

In the Middle Ages, Jews in the Islamic diaspora spoke a dialect of Arabic, which they wrote in a mildly adapted Hebrew script  (rather than using Arabic script).

This phenomenon is called Judaeo-Arabic and may be compared to both Ladino (Judaeo-Spanish) and Yiddish (Judaeo-German).

Some of the most important books of medieval Jewish though were originally written in Judaeo-Arabic, as well as certain halakhic works and biblical commentary.  Only later were they translated into medieval scientific Hebrew so that they could be read by the Ashkenazic Jews of Europe.  These include:

 Saadia Gaon's Emunot ve-Deot, his Tafsir (biblical commentary and translation), and his siddur (the explanatory parts, not the prayers themselves)
 Solomon ibn Gabirol's Tikkun Middot ha-Nefesh
 Bahya ibn Pakuda's Hovot ha-Levavot
 Judah Halevi's Kuzari
 Maimonides' Commentary on the Mishnah, Sefer ha-Mitzvot, Guide to the Perplexed, and many of his letters and shorter essays.

References

Judaism
Middle East
Semitic languages

Judeo-Arabic dialects


The kilometre is a common unit used for longer distances on Earth. The international unit for measuring distances is the metre and a kilometre is 1000 metres. It is used in most countries for measuring road and sea distances. In the UK and the USA, the statute mile is used more than kilometres for road distances and the nautical mile for sea distances.

It is often used to measure the speed of cars, planes and boats by saying how many kilometres it can travel in an hour. This is shown as km/h.

It is also spelled kilometer. This spelling is used in American English.

One kilometre is 0.6214 miles (1093 yards or 3280.84 feet). This means that one mile is 1.6093 kilometres.

One kilometre is the approximate distance a healthy adult human being can walk in ten minute

A kilometer is sometimes called a klick

Related pages
 Yard (unit of length)

Units of length

Kilometre


A blast furnace is a special type of furnace for smelting iron from ore. Blast furnaces are very large. They can be up to  tall and  in diameter. The blast furnace is the biggest chemical reactor. Blast furnaces are also called high ovens.

A blast furnace is usually built with a steel case and bricks made of magnesium oxide or other refractory material inside the case. The hot furnace cannot melt these bricks. The furnace is cooled with water running inside part of the case and bricks.

The process of making iron is simple. Iron ore is basically iron oxide.  Iron is made by removing the oxygen. This leaves crude iron called pig iron. This process of removing oxygen is called smelting. Carbon is used in the reduction process, with the ore heated to a high temperature. Carbon easily takes the oxygen off the ore in high temperatures.

Process
Ore, limestone and carbon in the form of coke are put into the top of the blast furnace in layers. At the same time, hot air called "wind" is blown inside the furnace. Special nozzles called "tuyeres" are used to put the air in the furnace. The nozzles are at the bottom of the furnace. This process is called "blasting". It is why it is called a "blast furnace". The coke ignites (lights on fire) and burns. This creates carbon monoxide because there is not enough oxygen to make carbon dioxide. The carbon monoxide then reduces the metal oxide to the metal and makes carbon dioxide. This process is used to make iron. The limestone forms a substance called slag with the rock of the iron ore.

The bottom part of the furnace is called the hearth. When it has filled with liquid pig iron and slag, the slag is removed. This is called skimming. Slag is lighter than iron and does not mix with iron. It floats on top of the iron. A hole is made in the hearth at the level of the slag with a special drill.  The liquid slag moves out through the hole into a container called slag pot. The iron is then drained from the hearth. This is called tapping. A hole is made at the bottom and the liquid pig iron comes out.  It is either used directly for steelmaking, put into a special railway wagon called torpedo car or made into molds. When all the pig iron has been removed, fire-resistant clay is used to close the two holes. The clay becomes solid very quickly because of the high heat.

The pig iron contains some 4% of carbon and it would be too hard and too brittle to use. The extra carbon must first be burned away. The pig iron is refined into steel by decarburizing (burning the extra carbon off of) it. A modern method for decarburizing the pig iron and refining it into steel is basic oxygen furnace. Historically there has been other methods as well, such as Bessemer converter, open hearth furnace and puddling furnace.

The gases rise up and are collected on the top of the furnace. As the gas contains a lot of carbon monoxide, it is a valuable fuel. The gas collected on the top of the blast furnace is called blast furnace gas. It is then washed and dried and all solid particles such as soot or ore dust are collected. The gas is then burned in special ovens called Cowper stoves or hot blast stoves into carbon dioxide. The heat from burning the blast furnace gas is then used to pre-heat the blasting air, "wind", which in turn is blasted into the blast furnace itself.

The slag is not waste. It can be used in various ways. It can be made into bricks and used for construction, or it can be mixed with concrete. Concrete which contains blast furnace slag is stronger than ordinary concrete and is almost pure white, where normal concrete is dirty grey.

A blast furnace can usually work for 10 to 20 years without stopping. This is called a "campaign."

Chemical example
At the temperature of 900-1600°C, a reduction with carbon occurs:

Now iron has been made.

Ores
Chemical processes

Blast furnace