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Pop Art

by Laura Reeves

What is pop art?

Pop art was an art movement originating in the mid-1950s in the UK. Artists in the USA were also exploring the same ideas at around the same time. Pop art is an abbreviation of 'popular art' and comes from popular culture. It was a celebration of Western consumerism, based on commercial and popular images. Pop art featured advertisements, packaging, comics, the movies, fast food, and household appliances.

How was pop art created?

A variety of techniques were used to create pop art, such as painting, silk-screen printing, collage, and sculpture. Many pop artists used these techniques, as well as combining them within the same image. Richard Hamilton (1922– ), a British pop artist, declared that pop art should be:

• popular (designed for a mass audience)
• transient (a short-term solution)
• expendable (easily forgotten)
• low-cost
• mass-produced
• young (aimed at youth)
• witty
• sexy
• gimmicky
• glamorous
• big business.

As we can see from this list pop art suggests a whole variety of themes and is extremely open-ended. There are many famous pop art themes.

Images of popular food of the 1950s and 1960s were used, as they were common objects, recognizable by all. For example Andy Warhol's painting called 200 Campbell's Soup Cans (1962) is one of 32 paintings of the whole range of Campbell's soup. The sculpture by Claes Oldenburg called Two Cheeseburgers with Everything (1962) is a reproduction of typical American food, popular to many.

Icons of the music and film industry were used a lot in pop art. This was an exploration of fame and glamour, and sometimes death within popular culture. Andy Warhol produced many images of Marilyn Monroe after the tragedy of her death in 1962. His silk-screen print called Marilyn (1967) is a portrait of Marilyn Monroe in which he uses bright colours instead of realistic ones. He was trying to show her colourful, joyful public personality by changing the colours. The painting I'm Dreaming of a White Christmas (1967) by Richard Hamilton shows an image of Bing Crosby, whose hit song gives the painting its title. Bing Crosby had mass appeal as a Hollywood film star.

Comic-strip style images were typical of the work of Roy Lichtenstein. The themes within his comic strips were often inspired by the drama of life, romance, and war. His individual painting style using flat colours, bold outlines, and small dots made the comic-strip paintings appear as though they had been printed – the technique which is normally used for actual comic strips. His painting Girl with Hair Ribbon (1965) shows an attractive, glamorous woman with blonde hair and blue eyes. She looks at the viewer in an anxious manner, which suggests she is a heroine in trouble. This image could quite easily be a clip from a film starring an American beauty.

Some pop artists used ordinary, everyday objects as a theme for their art, sometimes actually incorporating found objects into their work. Such ordinary items were instantly recognized by everyone. This made the artwork relate closely to popular culture. For example, the wax painting called Three Flags (1958) by Jasper Johns shows three US flags – images instantly recognized universally. The mixed media image Toy Shop (1962) by Peter Blake, shows a young, popular image of a toy shop's door and a window full of real items found in a typical toy shop. In the collage Just what is it that makes today's homes so different, so appealing? (1956) Richard Hamilton manages to combine many aspects of popular culture. It shows a room containing household appliances, furniture, food, an attractive man and woman shown as sex symbols, an advertisement for a comic, and a theatre seen through the window.

Who were the pop artists?

Pop art was at its most famous in Britain and the USA. Some of the well known US pop artists include:

• Swedish-born Robert Rauschenberg (1925– ), who is well known for using real objects within his paintings. He has also produced silk-screen prints which represent subjects from the USA, such as President Kennedy, the Vietnam War, and the exploration of outer space
• Jasper Johns (1930– ), who painted obvious, repetitive objects such as flags, targets, numbers, and letters
• Claes Oldenburg (1929– ), who is well known for his sculptures of enlarged objects from the consumer society, such as food and household appliances
• Roy Lichtenstein (1923–1997), who painted comic strips to portray the drama of life, romance, and war
• Andy Warhol (1928–1987), who painted and printed images of everyday life, labels, social icons, and food
• James Rosenquist (1933– ), who randomly combined images from popular culture, such as food, people, and everyday objects in a billboard style.

Some of the well known British pop artists include:

• Richard Hamilton (1922– ), who painted and printed popular subjects such as pop music, advertising slogans, technology, and film
• Peter Blake (1932– ), who did collages and paintings of consumer goods such as toys, postcards, and record sleeve designs, as well as photographs of famous actors
• Allen Jones (1937– ), who generally used images from 1940s US culture.

Questions and answers

Q1 Where does the term 'pop art' come from?
A1 From 'popular art' – pop art took its imagery from popular culture.

Q2 Where and when did pop art originate?
A2 In the UK and USA in the mid-1950s.

Q3 The British pop artist Richard Hamilton defined 11 features of pop art. What were they?
A3 Hamilton said pop art should be: popular, transient, expendable, low-cost, mass-produced, young, witty, sexy, gimmicky, glamorous, big business.

Q4 Which pop artist famously produced a silk-screen print of Marilyn Monroe and paintings of Campbell's soup?
A4 Andy Warhol.

Q5 What is US pop artist Roy Lichtenstein particularly known for?
A5 For painting comic strips to portray the drama of life, romance, and war.

Q6 Go to the library or use the Internet to find a reproduction of the painting M-Maybe (A Girl's Picture) (1965) by Roy Lichtenstein. What are the qualities of the female image and why does it make the image popular?
A6 The female is young, attractive, and glamorous, and looks like a Hollywood star. The image is made popular by the qualities that it suggests: fame, money, the movies, and comic strips.

Q7 Find a picture of the sculpture Soft Toilet (1966) by Claes Oldenburg. Why is the sculpture pop art?
A7 It is an everyday object recognized by all. It is also witty and gimmicky.

Q8 Find a picture of the collage Girlie Door (1959). With popular culture in mind, why do you think that Blake has stuck photographs of glamorous women onto a door?
A8 The photographs are almost like a tribute to the cult of the star. Many people collect souvenirs within our culture and these are photos of rich, famous, and beautiful female stars, who are always evident in popular culture.

Q9 Find a reproduction of the painting F-11 (1965) by James Rosenquist. Identify the objects within the image and then decide what theme these objects represent. Why is this relevant to pop art?
A9 The painting shows a child under a hairdryer, a light bulb, an atomic cloud, a racing tyre, and a jet-fighter plane. These objects represent the theme of technology and scientific development. It is relevant to pop art because they are things which are recognized within British and US culture.

Q10 Find a picture of Warhol's screen print and painting Tuna Fish Disaster (1963). What aspects of popular culture are used here?
A10 The image shows tins of tuna fish and the two women who died of botulism as a result of eating from those tins. The words 'Seized shipment: Did a leak kill?' indicate a newspaper headline. Food brands and the news are aspects of popular culture.

Check it out!

(1) Select a packaged food product from the kitchen cupboard or the supermarket. Divide a piece of paper into four and draw your item into each quarter using a bold, black outline. Include the lettering but do not include small details. Make sure the food product is big enough to fill most of each section. Colour each picture in different colours. You do not have to use realistic ones. Make sure each background is a different colour from the food to ensure it stands out.

(2) Select a picture from a magazine or newspaper of your favourite sports person, band member, actor, or actress. Copy the face of this person using a bold outline and make sure you include some shadow outlines too. Choose five bright colours, and colour in the face and background. Use one colour for the hair, eyebrows, eyelashes, and facial hair (if any). Use one colour for the eyes, lips, and nostrils. Use one colour for the pale tones of skin and one for the shadows on the face. Use the final colour as a background.

(3) Choose any of Roy Lichtenstein's pictures from a comic strip. Draw three or four box outlines to be used as the stages of a comic strip. Copy Lichtenstein's picture into the first box and then make up the rest of the story in the remaining boxes. Try to mimic Lichtenstein's style and colours when drawing your own stages of the comic strip. You can use speech bubbles or a line of writing at the top of each box to help you tell the story.

(4) Make a collage of any aspect of today's popular culture. This can be done by sticking magazine or newspaper cuttings, postcards, stickers, food packets, and so on, onto paper.

External and Internal Fertilization

by Mary Jones

Introduction

Fertilization is the joining together of the nucleus of a male gamete and the nucleus of a female gamete. It is a very important stage in sexual reproduction. It happens in plants (inside flowers) and in animals.

In some animals, such as frogs and most kinds of fish, the male and female gametes meet and fuse outside the animals' bodies. This is called external fertilization. In other animals, such as humans and all other mammals, birds, reptiles, and some insects and fish, the male and female gametes meet and fuse inside the female's body. This is called internal fertilization.

External fertilization in frogs

Frogs are amphibians. Adult frogs spend most of their time on land. In the spring, they find their way to water. Male frogs croak to attract female frogs to them. Sometimes, you can find hundreds of frogs all together in a pond at this time of year.

The females look especially fat, because their bodies are full of eggs. These are the female sex cells (female gametes). The male frogs try to find a female who is ready to lay her eggs. One male frog then grabs a female around her shoulders, and hangs on tight to her back.

The female frog then lays her eggs into the water. Each egg is a single cell, but it is much larger than most cells, so you can easily see the eggs, which are called frog spawn, with the naked eye. The eggs are large because they contain yolk, which contains nutrients on which the developing tadpoles will feed for the first few days of their life.

As the female lays her eggs, the male frog releases thousands of sperm into the water. The sperm are much smaller than the eggs, much too small to see without a good microscope. The sperm swim to the eggs and fertilize them. Only a few sperm will find an egg. The rest just die.

Each egg has a layer of jelly, called albumen, around it. This swells up very quickly once the eggs are in the water, making a slippery, protective coating around the egg. This jelly will also protect the tadpole as it develops inside it.

The male and female frogs do not look after their eggs. Many of the eggs are eaten. The tadpoles hatch after several days. They are eaten by many different predators, such as fish, newts, and great diving beetles. Only a very tiny proportion of the eggs that the female frog laid will eventually become adult frogs.

Internal fertilization

Animals that reproduce on land cannot use external fertilization. If a female mammal laid her soft eggs onto the dry ground, they would just shrivel up and die. And if they had a shell on them, the sperm would not be able to get in and fertilize them. In any case, sperm cannot swim on land, and they would dry up. External fertilization can only happen in the water.

So animals that live on land use internal fertilization or – like frogs – they go back to the water to reproduce. The male's sperm are put into the female's body, where they remain moist and safe. The sperm can then swim to find the female's eggs and fertilize them. In a human, the sperm fertilizes the sperm in the woman's oviduct (the tube leading from the ovary, where the eggs are made, to the uterus, where the baby will develop).

Internal and external development

In some animals that use internal fertilization, the fertilized egg stays inside the mother's body while it develops. Humans and most other mammals do this. The developing baby is fed through the placenta from its mother's body as it grows. It is kept safe from predators. In other animals that use internal fertilization, the fertilized egg is laid outside the mother's body. Birds and reptiles (for example, crocodiles) do this. The developing baby is fed from food stores inside the egg as it grows. Often, the parents sit on the eggs while they are developing, to keep them warm and to protect them from predators.

Questions and answers

Q1 What is the difference between external fertilization and internal fertilization?
A1 In external fertilization, the sperm and egg fuse together outside the animals' bodies. In internal fertilization, the sperm and egg fuse together inside the female's body.

Q2 Name two animals that use external fertilization
A2 Frogs and fish.

Q3 Describe two reasons why the eggs of a frog are larger than the sperm
A3 Eggs contain nutrients to feed the developing tadpole for the first few days after fertilization, but sperm only need enough nutrients to give them energy to swim to an egg. Eggs are covered with a layer of jelly to protect the developing tadpole, but sperm are not.

Q4 Why are more sperm than eggs produced by mating frogs?
A4 A lot of the sperm will not find an egg, so many sperm are needed to make up for the 'wasted' ones. Moreover, sperm are less 'expensive' to make than eggs, because they do not need to contain food stores like eggs do.

Q5 Name two animals that use internal fertilization
A5 Any mammals, birds, or reptiles.

Q6 Why can external fertilization only take place in the water, and not on land?
A6 The eggs and sperm would dry out on land.

Q7 Birds' eggs have shells. Do you think the shell grows around the egg before or after it is fertilized? Explain why you think this
A7 The shell grows around the egg after it is fertilized. Otherwise, the sperm would not be able to get in and fertilize it.

Q8 Does internal fertilization always mean that development of the embryo will take place inside the mother's body?
A8 No. In birds and reptiles, the egg is fertilized inside the mother's body and then laid, so that development of the young animal takes place outside the mother's body.

Q9 Most animals that use internal fertilization produce fewer eggs and sperm than most animals that use external fertilization. Suggest why this is so
A9 In external fertilization, the sperm have to swim through a lot of water to find the eggs, so many of them get 'lost' and wasted. In internal fertilization, it is a bit easier for the sperm to find the egg, so fewer are wasted. In external fertilization, many of the eggs may be eaten by predators. In internal fertilization, they stay inside the mother's body where they are protected.

Q10 Mammals have internal fertilization, and internal development. Birds have internal fertilization, but external development. Suggest why the eggs of mammals are smaller than the eggs of birds
A10 The mammal egg has only to contain enough nutrients to feed the fetus for a few days, until it grows a placenta. The bird's egg has to contain enough nutrients to feed the baby bird for many days or weeks, until it hatches.

Check it out!

Frogs and toads lay their eggs in late February and March. Try to find a pond where frogs or toads are spawning, and watch their behaviour. There are quite a lot of animals that live in water and use internal fertilization. Find out about two different animals that do this. Why do you think it is an advantage to them to use internal rather than external fertilization? Sticklebacks are an example of a kind of fish that use external fertilization, but then take care of their eggs and young. Find out if they lay less, more, or the same number of eggs as fish that do not care for their young, and try to explain your findings.

The History of the Periodic Table

by David Moore

Introduction

Scientists had for many years been trying to arrange the elements in groups, in particular by sorting them into groups having similar chemical properties. However, not all of them had equal success.

Johann Döbereiner

In the first half of the 19th century the German chemist Johann Döbereiner had arranged most of the known elements into groups of three – or triads. For example, he had a triad consisting of lithium, sodium, and potassium, and another of chlorine, bromine, and iodine. He showed that when written in order of increasing atomic mass, the middle one had a mass equal to the average of the two elements placed on either side of it, and also had properties lying somewhere between those of the other two. Döbereiner's work encouraged other chemists to look for trends between the elements.

John Newlands

In 1866 the English chemist John Newlands proposed his 'Law of Octaves', in which he suggested that if the elements were arranged in order of increasing atomic mass, then the eighth element in the series had similar properties to the first. So, as in music, patterns repeated themselves rather like musical octaves. His theory was criticized heavily at the time for three main reasons. It assumed that all the elements had been discovered – there were no gaps left for elements as yet undiscovered. On four occasions the law also had to put two elements together in only one space in order to get them to fit. Finally, elements with dissimilar properties were placed in the same family.

Dmitri Ivanovich Mendeleyev

In 1869 the German chemist Lothar Meyer plotted graphs of physical properties against atomic weights and showed that there were periodic properties. However it was only when the Russian chemist Dmitri Ivanovich Mendeleyev published his version of the periodic table, also in 1869, that the ideas of periodicity and periodic properties became fully established.

Mendeleyev came up with a version of the periodic table that is very similar to that which we know today. He made important assumptions. He correctly assumed that all the elements had not been discovered and so left gaps and spaces for them. Although he had arranged the elements in order of increasing atomic mass, he was not averse to switching round the positions of elements if their properties did not fit those of the group in which they were placed. The best examples of these are iodine (relative atomic mass 126.9) and tellurium (relative atomic mass 127.6). If he used increasing mass, iodine should have come before tellurium. However, because their properties would not fit in that order, he swapped their positions – their reactions were now correct. (When protons were discovered and the elements arranged in order of increasing proton number, it was indeed found that tellurium should come before iodine, as tellurium has 52 protons, while iodine has 53.)

Mendeleyev could also predict accurately the properties of elements before they had been discovered, from their position in the group. He knew the properties of silicon and tin, but the element between them in the group had not been discovered. In 1871 he predicted its properties, both chemical and physical, as well as its atomic mass. The element was germanium – discovered in 1886 by C A Winkler.

Mendeleyev also proposed that Periods IV, V, VI, and VII should contain more than seven elements and divided the spaces in two in order to fit in the other elements. These have been moved in the modern form into a separate block – the transition elements.

The periodic law of Mendeleyev stated that 'the properties of the elements are a periodic function of their relative atomic masses'. This allowed him to summarize the properties of the elements and classify them into groups with similar properties, and also enabled him to make predictions about known and unknown elements. During the 20th century chemists arranged the elements in order of atomic number (proton number) and so now 'the properties of the elements are a periodic function of their atomic number'. With very few exceptions this made little change to the periodic table proposed by Mendeleyev in 1869.

Questions and answers

Q1 Why did Döbereiner fail to produce a suitable periodic table?
A1 Because not all the elements had been discovered when he produced his table and he failed to leave gaps for them.

Q2 What is a periodic property?
A2 One that repeats itself at regular intervals.

Q3 Why did Mendeleyev think that Periods I, II, and III should only contain seven elements?
A3 The noble gases had not yet been discovered. They constituted an entire new group.

Q4 Why is it important to know the history of the periodic table?
A4 It allows us to understand the fundamental principles behind it and so use it more effectively.

Check it out!

Try and find out what Mendeleyev's original periodic table looked like. Compare it with a modern version. What are the differences?

The Justice System

by Paul Smythe

There are two types of justice.

Social justice involves everyone's right to be treated in the same way. Such rights are guaranteed by the law and are often written into the country's constitution. Such rights involve equal and fair access to education, to housing, employment, and health care.

Individual justice is a response to a crime that an individual person has committed. The punishment, which should be fair and appropriate, will be different depending on the individual and the crime committed.

The right to justice is often, though not always, enshrined in a constitution or set of rules. Historically, these gave justice to certain groups but not to others. The Magna Carta (1215) said, 'to no one will we sell, deny, or delay right or justice', but this did not include people who worked for landlords. The European Convention on Human Rights, incorporated into British law by the Human Rights Act of 1998, came into effect on the 2 October 2000. Its aim is to secure justice for all.

Even today, many people around the world do not have equal access to justice. This may mean that they are denied certain basic rights or that they are arrested without charge or explanation. Their case may be tried in court without giving them the opportunity to hear the charges against them, or a chance to defend themselves. There have been many instances in the UK and worldwide where people have been imprisoned wrongly. This is known as a miscarriage of justice.

Issues of fairness and of right and wrong are not always clear. For example, when Robin Hood robbed from the rich to feed the poor, he was actually breaking the law even though his cause was fair. Robin Hood was motivated by a good cause, but were his actions just? In modern society, people break the law to free animals that are being used for experiment, they block roads, and chain themselves to buildings and to trees to protest about the destruction of the environment. Military groups in Northern Ireland use the bomb and bullet in support of their cause. Where do we draw the line – when is a cause just and when is it unlawful?

The legal system

The legal system is designed to uphold people's rights, to give people protection, and to deal with those who choose to break the law. Everybody has a right to justice or fairness; even those suspected of crimes have rights to ensure that their case is heard fairly and without prejudice (any prejudgement). A defendant is 'innocent until proven guilty'. It is the job of the prosecution to prove that the defendants committed a crime; it is not for the defendants to prove that they did not commit the crime, although obviously they will want the opportunity to defend themselves.

A police officer who believes that a person has broken the law may use the power of arrest – this may involve taking the individual to a police station where he or she is likely to be questioned. If the police feel that they have enough evidence, they may charge the individual with a particular offence. The Crown Prosecution Service (CPS) will consider the evidence, and if they feel that there is a case against an individual and that there is a chance of a conviction, the case will be brought to court. The police uphold the law, but they do not decide whether the defendant is guilty, or set the punishment – this happens in a court of law.

There are three types of court in England, the magistrates' court, crown court, and juvenile court.

Magistrates' court

Magistrates or Justices of the Peace (JPs) are members of the public who are not trained in law, but who are considered to be good citizens. They are usually older people who have experience of life and are therefore considered able to pass judgement on others. Magistrates (there are usually three of them) consider minor cases, perhaps involving traffic offences, or crimes for which a fine may be given. If a case is more serious, it will be passed on to a crown court. At the present time, a defendant can insist that his or her case is heard at a crown court before a judge and jury, but this may well change in the future. It has been suggested that this decision should be made by the magistrates to prevent unnecessary cases, which could be costly, going to a crown court. The magistrates will hear the case, decide upon a verdict (decide if the defendant is guilty of a particular offence), and pass sentence (decide on an appropriate punishment).

Crown court

In a crown court the case is heard before a jury (usually 12 members of the public). Barristers (lawyers) will present the case for the prosecution and defence; they will call witnesses to provide evidence that the defendant is either guilty or not guilty. After the case has been heard, the jury will retire to another room to decide upon a verdict. A judge may insist on a unanimous verdict (where all agree) or majority verdict (at least 10 of the 12). The judge is there to make sure that the case is heard fairly and to uphold points of law. The judge will also decide on an appropriate sentence if the defendant is found guilty.

People over 18 may be called to do jury service. This is a compulsory duty though there are certain circumstances when a person may be excused.

Juvenile court

This court deals with cases where the defendant is under 18 years of age, although serious cases such as murder will be heard in a crown court regardless of the defendant's age.

The law states that children under ten years old are unable to distinguish between right and wrong, and therefore they are considered to be under the legal age of responsibility. The 1998 Crime and Disorder Act states that children between 10 and 13 years of age can be held responsible for their actions.

Most cases are open to the public. People can sit in the court and watch the process of justice as it happens. In addition, the newspapers are generally free to report what they see and hear in court. In the UK, unlike the USA, no cameras are allowed to record what goes on in court. In special cases, where the safety of an individual is at risk or where there is a case involving children, the case may be heard 'in camera', which means that the media cannot report the names in, or the events of, the case.

Questions and answers

Q1 What does justice mean?
A1 Justice involves fairness – fair and equal opportunity; the ability to enjoy basic human rights. Justice also involves using authority to support right and to deter wrong.

Q2 What is social justice?
A2 Social justice is about every person's right to enjoy basic rights. This includes an equal and fair access to housing, employment, education, and health care.

Q3 What is individual justice?
A3 This involves treating a person in a fair way – if a person is found guilty of a crime, society believes that it is only fair to the victim to punish the offender. This also acts as a deterrent to others who may consider offending.

Q4 How does society make clear what is fair and unfair, what is right and wrong?
A4 Many countries have a constitution – a set of rules that identify what is fair and what is not. All countries have laws that establish what is unacceptable behaviour and identify how it will be dealt with.

Q5 Why is it that some people do not have equal access to justice?
A5 In some countries there is no constitution, or the system of law and its enforcement is corrupt. In some situations, certain groups are denied equal access to justice.

Q6 How can issues of right and wrong, lawful and unlawful, become clouded?
A6 Sometimes, natural justice and the law of the land conflict. It is possible for a person to do something that he or she believes is right and good, but which is illegal. It is unlawful to take a person's life, even if that person is terminally ill, in great pain, and wants to die. Although this 'mercy killing', or euthanasia, is a crime, some people consider that it is an act of human kindness.

Q7 What is the purpose of the legal system?
A7 The legal system is designed to protect people's rights, to keep people safe, and to punish those who break the law. It is a system of justice which has procedures that are designed to ensure that the process of hearing a case is fair to all.

Q8 Why might a person want his or her case heard before a judge and jury in a crown court, rather than magistrates' court?
A8 A person may feel that a jury would be able to relate and sympathize with the defendant more. If a jury does not agree, it may be that the judge will have to dismiss the case.

Q9 Why do you think that the government wants to remove the right of people to choose whether their cases should be held in a magistrates' court or a crown court?
A9 It is more costly to hear cases in a crown court – some cases that could easily be dealt with in a magistrates' court, take up time in a crown court. The government might argue that the best person to make this decision is the magistrate.

Q10 What is the legal age of criminal responsibility? Do you think this age should be increased, decreased, or stay the same?
A10 It is considered that by ten years of age, children are capable of distinguishing between right and wrong, and can therefore be found responsible for their actions.

Check it out!

(1) Do you think that people should have the right to decide whether their case should be held in a magistrates' court or a crown court. Do you think that a person has the right to have his or her case heard in front of a jury? What advantages are there to having a case heard before a jury?

(2) Use the Internet to find out more about the work of Amnesty International – a group that tries to secure justice for those previously denied it.

(3) Find out more about euthanasia. In your opinion, is euthanasia a crime or an act of human kindness?

Textile Processes

by Jane Hodges

Introduction

All items made from textiles go through several different processes. The initial material is designed and constructed and may be decorated. It can then be used to produce a whole range of different things including soft furnishings, clothes and accessories, car seat covers, and toys. Virtually every end product involves the use of a sewing machine or overlocker at some stage of its manufacture. Domestic and industrial versions of both are available.

Suitability of design

Before construction begins, there are many different things to take into consideration. While producing design work, you need to check that it is suitable for the purpose for which it is intended. Some fashion designs can look excellent on paper, but would be totally impractical for everyday use. Fashion and textile designers are usually working to a brief from a customer, and they need to make sure that their designs fulfil the requirements of the brief. You also need to look at how easy it will be to make, and consider what construction techniques you might use. Safety is another important feature, particularly if the item is for a young child. In this case, you need to take care that there are no small pieces that a child could choke on or swallow. Fastenings are another important feature of most items, and you need to consider how and where you will incorporate them. Finally consider its aesthetic qualities – does it look good?

Suitability of material

Different types of fabrics are suitable for different purposes, and it is vital that this is taken into account while planning a design. Does the fabric need to be easily washable, soft to the touch, warm to wear, hard wearing, stretchy, waterproof, or perhaps flameproof? Is it expensive? If you are basing a pattern on an existing item, you need to make sure you use materials with similar qualities. For instance, you would have difficulties trying to make a copy of something made out of stretch fabric if you were using a fabric that was not as stretchy or only stretched one way, as it is unlikely to fit properly.

Suitability of construction methods

Having decided what to make and what material to use, the next step it how to construct it. If you have produced your own design, you will probably want to make your own pattern. It is a good idea to look carefully at similar items and see how they have been constructed. You could then base your pattern on one of these and adapt it to fit your design, but remember to make allowances for things like gathers, pleats, darts, and seams. Professional tailors use block patterns for clothing. These are sets of basic shapes for each figure size or individual person, which they adapt until they get the look that they want. You can also use a commercial pattern and adapt this to your own ideas and designs. There are lots of patterns available for clothing and some pattern companies also produce patterns for toys and soft furnishings. Clothing patterns come in a range of different sizes and also include layout plans, instructions for actually making the item, and how much fabric to buy, so for the novice they can make a good starting point. They also often state what initial level of skill you need to complete the item.

Cutting out

If using a pattern, follow the instructions carefully. Check the fabric to see if it has a one-way pile or grain and to see which is the right side – some fabrics stretch one way and not the other. You will need to match stripes or checks. Lay the pattern pieces on the fabric. Check whether there is a seam allowance on the pattern and if not, allow 2.5 cm all the way around. Note how many fabric pieces need to be cut from each pattern piece. There is a grain line on commercial patterns, and you must make sure that this is parallel to the selvedge (the finished edge of the material). Check which pieces need to go along the fold. Pin the corners first and then pin every 10 to 15 cm. It is a good idea to put the pins in with the points facing towards the edge of the material, because this holds the fabric and pattern flatter. Cut out the pieces, keeping the fabric as flat as possible and making sure to cut around balance marks (diamond or double diamond shaped symbols).

Once you have cut out your pieces, it is easier to complete surface decoration before sewing together. This may include printing, embroidery, and appliqué. If you are making clothing, you will need to stitch things like darts at this stage as well.

Next you need to think about what stitches you are going to use. Pin and/or tack the pieces you are going to sew together. For most fabrics, you can use either a plain stitch on an ordinary sewing machine or use an overlocker. Stretch fabric is best sewn with a stretch seam, or on an overlocker. An overlocker is particularly good for stitching seams in stretch fabric. It stitches and neatens the seam and cuts off the excess fabric all at the same time. If you look at the seams in commercially produced clothing, they have usually been produced with an overlocker. If you have used a sewing machine, you should check whether you need to stop the edges of your fabric from fraying. Zigzag stitching along the raw edges will do this. Regular ironing of seams during construction is also a good idea.

Questions and answers

Q1 What does an overlocker do?
A1 It stitches and neatens the seam and cuts off the excess fabric all at the same time.

Q2 What sort of factors do you need to take into account when choosing fabrics?
A2 Does the fabric need to be easily washable, soft to the touch, warm to wear, hard wearing, stretchy, waterproof, or perhaps flameproof? Is it expensive?

Q3 How many centimetres should you allow for a seam allowance?
A3 2.5 cm.

Q4 At what stage during construction is it easier to do surface decoration?
A4 After cutting out and before sewing together.

Q5 What is stretch fabric best sewn with?
A5 A stretch seam or an overlocker.

Q6 Before laying pattern pieces on a fabric, what do you need to check?
A6 Whether the fabric has a one-way pile or grain, whether it stretches one way, whether you need to match stripes, and which is the right side.

Q7 Why might you use zigzag stitching along the raw edge of fabric?
A7 To stop it fraying.

Q8 When pinning on a pattern, how far apart should the pins be?
A8 10 to 15 cm.

Q9 What are block patterns?
A9 Sets of basic shapes for each figure size or individual person.

Q10 What is one safety aspect that you need to bear in mind when designing for a small child?
A10 That there are no small pieces that it would be possible for a child to pull off and choke on or swallow.

Check it out!

Producing your own textiles.

Consider the following before you start:

Design

sources

• look at existing items
• fabrics
• nature, buildings, landscapes, etc

suitability

• is it practical – is it easy to make and does it include details like fastenings and seams?
• is it safe – particularly if intended for a young child or for use in a kitchen
• is it fit for the purpose for which it was intended
• does it meet the customer requirements.

Patterns

• commercial patterns – quite a wide range available, which you could adapt to your own designs
• an existing item – this could be copied and adapted to your own designs
• your own design – tailors usually work from basic block patterns for clothing; it is also possible to work out your own patterns, but do this carefully and remember to allow for seams and fastenings.

Cutting out

• check for one-way pile, stripes, checks, one way stretch, right side of the fabric
• pin corners first, then other pins 10–15 cm apart
• remember to leave seam allowance
• keep fabric as flat as possible while cutting out.

Construction

• see if surface decoration can be done first
• darts, pockets, fastenings
• pin and/or tack seams ready to sew
• sewing machine – plain seams (nonstretch fabrics), zigzag for neatening seams and appliqué, various embroidery stitches
• overlocker – stitches, trims, and neatens seams (useful for stretch fabrics as well).

Now try:

(1) Research Celtic patterns and then produce some of your own designs based on these.

• Draw out one of your designs in biro and then turn the paper over.
• Trace the design through, then use fabric crayons to colour it in.
• Iron this design onto synthetic fabric, following the fabric crayon instructions.
• Sandwich a piece of wadding between your design and a spare piece of fabric.
• Pin together and then tack from one corner diagonally across to the other. Repeat the tacking for the remaining corners.
• With embroidery thread use backstitch to go around the shapes on your design. When complete, this can be made into a cushion. To do this:
  • put the two main cushion pieces together with the right sides facing each other.
  • pin and/or tack and using a sewing machine, sew around the pieces, leaving an 8 cm gap in the middle of one side. When starting and finishing, sew a couple of reverse stitches to fasten the stitching. To make neat corners, leave the needle in the fabric, lift the machine foot, turn the fabric, drop the foot, and continue sewing.
  • once sewn, trim the seams across the corners (do not go too near the stitching), and then turn the cushion the right way out, gently using a pair of closed scissors to push the corners out.
  • Stuff the cushion with polyester filling and then pin and hand sew the gap. Ladder stitch is good for this (take a small stitch from the folded edge then go straight across to the other side and take another small stitch – continue in this way.

(2) Research different construction ideas and design ideas for bags. Then produce a series of designs for an appliqué bag based on simple shapes like squares, triangles, and rectangles. Choose one of the designs and draw out full size. Use this to produce a series of patterns for each of the colours of fabric you intend to use. You can use bought fabrics, but you could also try colouring your own fabrics, for example with a sponge and fabric paint (experiment with some different techniques before you start). Lay your pattern pieces on the fabric. Cut out, then begin putting your appliqué patterns together. Machine zigzag is good for stitching these pieces on, but tacking them together first is a good idea. Once the surface decoration is finished, this can then be made into your bag.

(3) Research and then produce some design ideas for textile items that will help children to learn. Ideas might include an alphabet book, a play mat based on a clock, or with fastenings to help them to learn to tie shoelaces, fasten buttons, etc. Choose one design and produce patterns and a final piece based on this.

(4) Research and then produce design ideas for some simple loose summer clothing. Look at different fabrics and then carefully work out your pattern pieces. If this is your first attempt, you should either base your patterns on some existing clothing, or use/adapt a commercial pattern. It is also a good idea to do a trial run using cheap fabric, to see whether it fits.

Onomatopoeia, Euphony, and Cacophony

by Bethan Hobbs

What is your favourite word? Usually when this question is asked, people answer with words they like the sound of, rather than with a word they like the meaning of. Some words are simply lovely to say; they roll around your mouth and fall easily and musically off the tongue. Because we use words first and foremost as a means of communicating with people, we sometimes forget that they have qualities all of their own that are not necessarily related to their meaning.

In poetry in particular, the sound of words can be of equal importance to their meaning. That does not mean to say that the two cannot go together; often the sound of a word can enhance its meaning, which is the case with these three terms – onomatopoeia, euphony, and cacophony.

The music of words

Take a look at these two paragraphs.

The car came very fast round the corner, with clearly no time to brake before it hit the bus shelter. There was a horrible noise, as the metal of the bus shelter buckled and the glass fell from its frames. The car was in a bad way, with smoke and steam coming out of the bonnet. 'Someone call an ambulance!' I said.

The car came squealing round the corner, with clearly no time to brake before it smashed into the bus shelter. There was a wrenching crash and the sound of grinding metal as the bus shelter buckled and the glass cracked into splinters and fell, smashing from its frames. The car was a mangled wreck, with smoke billowing and steam hissing from the bonnet. 'Someone call an ambulance!' I roared.

Although both paragraphs are explaining the same event, the second version seems to be much more dramatic. The incident becomes more three-dimensional, almost with more 'flavour', as the events are brought more alive through the senses. That is because the second sentence has sound effects. The language has an aural quality, and includes words whose pronunciation suggests their meaning. In literature, a word whose sound seems to closely resemble its meaning is called onomatopoeic. Sometimes, onomatopoeia is also known as echoism, because the word's sound echoes its meaning. Examples of onomatopoeia are highlighted in bold in the second paragraph above. 'Hiss', for example, when spoken aloud, actually resembles the sound of steam, or more commonly, a snake. Other common examples of strictly onomatopoeic words are fizz, whirr, sizzle, and of course, snap, crackle, and pop!

However, there are also words in the extract for which their verbal sound is not an exact duplication of their nonverbal sound, but the similarity is still very strong because of the meaning of the word. Look at words such as billowing, grinding, and wrenching, as well as the others that are written in italics. In these examples, the connection between sound and pronunciation is more a product of the imagination than an echo of their created sound. However, these are still onomatopoeic because they produce a lively sound quality that enhances the intended meaning of the word.

Euphony and cacophony

Two other literary terms, that deal with the sound of words, are euphony and cacophony. Euphony is a term use to describe language that is simply pleasant to the ear, sounds that are smooth and musical. Cacophony, sometimes called dissonance, means the opposite. Words can be hard on the ear too, with jagged edges that almost 'snag' with the other words around them. Often in cacophony, words are made up of consonants rather than vowels, as consonants have harder, more clipped sounds, than the smooth, round sounds of vowels.

Again, take a look at these two examples:

• The cool water slipped silently by, with moonlight bobbing on its glassy skin. Smooth, round pebbles lay on the brook's floor, hugging the sand with comforting ease.
• The rat sat silently, its jet black eyes flashing furiously in the darkness. Its nest was a heap of festering rags, which stank of rot and disease.

These two paragraphs talk of very different subjects, but if you read the sentences aloud, you will find that the words, although not onomatopoeic, certainly reflect the subject matter. In examples of cacophony, the words can actually be quite awkward to say, and therefore sound harsh, like a wrong note or discord in a piece of music. By contrast, in euphony the words tumble out smoothly and easily, reflecting the melody of music. Using words in such a way, taking into account their sound quality, can make poetry, in particular, come alive in its meaning.

Questions and answers

Q1 Explain in your own words what onomatopoeia means.
A1 Onomatopoeia is the use of words which, in their pronunciation, suggest their meaning.

Q2 What other word is also used to mean onomatopoeia?
A2 Echoism.

Q3 Give three examples of words that are onomatopoeic and that are not included in this article.
A3 Bang, pow, zap, click, screech.

Q4 Why are words such as 'grinding' and 'mangled' considered onomatopoeic, even though the meaning of each word does not strictly resemble the sound it creates?
A4 These words maintain a dramatic aural quality, which adds to the effect of each word's meaning, even though it does not echo exactly the sound created.

Q5 Explain what euphony is.
A5 Words whose sounds are pleasing to the ear.

Q6 Explain what cacophony is.
A6 Words whose sounds are disagreeable to the ear.

Q7 Why are words made of consonants more likely to be included in writing that is intended to be cacophonic rather than euphonic?
A7 Because consonants make 'sharper', more 'jagged' sounds, which can create discord.

Q8 Explain why words using vowels are more commonly found in euphonic phrases than cacophonic phrases.
A8 Because vowels are softer, rounder, more open sounds, which do not create any friction in the sentence.

Q9 Referring to the two examples about the cool water and the rat, explain which one is euphonic, which is cacophonic, and why.
A9 The first example is euphonic, using words which are smooth and easy to pronounce, such as 'slipped', 'bobbing', and 'pebbles'. The second example is cacophonic, using harsher, more awkward to pronounce words, such as 'rat', 'silently', 'festering', and 'rot'.

Q10 Why do you think onomatopoeic words are often used in product advertisements?
A10 Because words that are onomatopoeic stand out more and are therefore more memorable. They almost jump out at the listener because they are more dramatic, almost three-dimensional, and can perhaps make a product come alive.

Check it out!

Take a look through some poetry and try to find examples of onomatopoeia, euphony, and cacophony. To help you, Alfred Tennyson and Robert Browning are particularly renowned for their skilful use of 'musical words'.

Ecosystems: Tropical Rainforests

by Garrett Nagle

Introduction

Tropical rainforests are among the world's most luxuriant ecosystems. However, they are also one of the world's most threatened environments. Tropical rainforests are found in hot wet tropical areas, close to the Equator. Hence, they are sometimes called equatorial rainforests.

Tropical rainforests are remarkable for the diversity of plants and animals that they contain. What is equally remarkable is how infertile the soil is. Rainforest soils have very few minerals (because the plants are using them), and rainforests have been described as 'deserts covered by trees'.

Tropical rainforests are the world's most diverse ecosystem, and one of the world's most important ecosystems. They contain a wide range of species. We call this genetic variety or biodiversity. They also absorb a huge amount of carbon dioxide and convert it to oxygen, helping to manage or reduce the greenhouse effect. However, as the rainforest is cut down, CO₂ is released into the atmosphere and there is less forest to absorb it.

Climate

Rainforests are close to the Equator so temperatures are high (26–27°C/79–81°F) throughout the year. The contrast between seasonal temperatures is low and there may be a difference of only 1–2°C/1.8–3.6°F between summer and winter temperatures. Daily temperature ranges, in contrast, are greater and there can be a difference of between between 10–15°C/18–27°F between day and night temperatures. Because of this low variation in temperature, the growing season lasts all year round. Annual rainfall is generally over 2,000 mm/79 in. This is caused by convectional rainfall. Humidity in the rainforests is consequently high, often at around 100%.

Soils

At the top of the soil there is a thin layer of humus. This is supplied with a continuous supply of leaves, which are broken down quickly by very active soil fauna. The accumulation of iron and aluminium gives the soil a red colour. In some cases the concentration of aluminium may form bauxite nodules. Under the hot, wet conditions fine clay and silicate particles are removed from the soil. There is also a loss of minerals, such as N, Ca, Mg, K, by leaching. The underlying bedrock is intensely weathered, so tropical soils are often deep, as well as infertile.

Vegetation

Vegetation in the rainforest is evergreen, allowing photosynthesis to take place all year round. It is layered, and the shape of the crowns vary with the layer, in order to receive light. Rainforests are very productive ecosystems. The ecosystem is diverse: there are as many as 200 species of tree per hectare (one hectare is the size of a rugby pitch), including figs, teak, mahogany, and yellow woods.

Nutrient cycle

The nutrient cycle refers to the cycle of nutrients (minerals) between the soil, the litter, and the vegetation. In the rainforest the nutrient cycle is easily disrupted. This is because once the vegetation is removed, nutrients are quickly removed from the system. This creates infertile conditions, even deserts.

Human activities

Over 200 million people live in the rainforest. The annual loss of rainforest is about 40 million acres – the size of England and Wales. This means that the rainforest is disappearing at one acre per second. The rate of deforestation in the 1990s was 50% higher than in the 1980s.

Destruction of the tropical rainforest

Tropical rainforests are being destroyed at an alarming rate throughout the world. The main reason for this destruction is population growth and the need to farm more land to feed the growing population. In addition, there are specific problems such as forestry, mining, and road building, which may destroy large areas of rainforest. Commercial farms, such as plantations and ranches, also lead to the destruction of large areas of forest. The variety of reasons is great, as shown in the table below.

Questions and answers

Q1 What is the tropical rainforest?
A1 It is a type of forest found in wet, tropical areas. It is the world's most diverse ecosystem, and one of the world's most important ecosystems.

Q2 Why is the rainforest so important?
A2 It contains such a wide range of species. We call this genetic variety or biodiversity. It also absorbs a huge amount of carbon dioxide and converts it to oxygen, so it helps to manage or reduce the greenhouse effect. However, as the rainforest is cut down, CO₂ is released into the atmosphere and there is less forest to absorb it.

Q3 Why is the rainforest so different?
A3 Because there is a year-round growing season due to constant warmth and moisture.

Q4 How warm is it?
A4 Usually over 26–27°C/79–81°F, without any seasonal variation.

Q5 How wet is it – and why?
A5 Annual rainfall is generally over 2,000mm – this is caused by convectional rainfall (the warm air rises, cools, condenses, and forms rain).

Q6 How many people live in rainforest areas?
A6 About 200 million people, many of them in cities such as Manous in the Amazon.

Q7 Why can the rainforest be described as a 'desert covered by trees'?
A7 Because the soil is infertile. If you remove the forest, the soil is removed quickly by rain.

Q8 Why is it removed so quickly?
A8 The rain is so intense and heavy. Without any vegetation to intercept the rain, the rain pounds the soil and washes it away.

Q9 At how fast a rate is the rainforest being destroyed?
A9 At a rate of 20 million hectares/40 million acres a year. This equates to an area the size of England and Wales every year. The rate works out at 0.5 hectares/1 acre per second.

Q10 What sort of trees are in a rainforest?
A10 Mahogany, teak, yellow wood, fig.

Check it out!

Contact your Local Council Offices. Find out what they are doing to preserve natural habitats in your area. Is there an Agenda 21 statement (this deals with sustainability, conservation)? Make a survey of your local area to find out how much woodland there is and if it has reduced in size during living memory.

The Domesday Book

by Martyn Whittock

What is the Domesday Book?

Domesday Book is the name given to the great survey carried out by William the Conqueror to record who owned land in England. It was written in 1086. This was 20 years after Duke William of Normandy defeated the English king Harold II at the Battle of Hastings (the Norman Conquest in 1066). The name Domesday means the 'Day of Judgement'. The book is first recorded with this name in about 1170, though it had probably been called this, by ordinary people, since soon after it was written. Others called it 'The Great Survey', 'The Book of Winchester' (the place it was originally kept), or 'The Great Description of England'. It was called the book of 'Judgement Day' because people believed that just as God knew everything about a person's life, so King William had found out everything about a person's land in 1086.

Why was it made?

King William spent the Christmas of 1085 in Gloucester. While he was there he held discussions with his leading supporters about who owned what land in England. This was important for William to know because land was given by the king and, in return, those given land had to provide him with knights to fight for him. Since the Norman Conquest the ownership of the land in England had changed a lot. Anglo-Saxons had lost their land to Normans and other foreign supporters of William. Now William needed to find out exactly what land everyone owned and what it was worth.

In 1085 this was particularly important to William because he thought England might be invaded from Denmark. To stop this he had gathered a large army. The cost of paying for this army needed to be shared out among the new Norman lords of England, so William needed a record of land ownership in England. The result was the Domesday Book.

Well-organized government

Teams of commissioners were sent into different parts of the country to collect the information. For each village, the priest, the reeve (an official), and six villagers gave information about their village. This was checked against what was already known.

Later a different group of officials visited each area to check the records made by the first commissioners. William made sure that nobody cheated him!

All the detailed facts and figures were then reduced to the most important information and written up in what is called 'Great Domesday'. The information for East Anglia was never edited and shortened and this still survives in what is called 'Little Domesday'. This is even more detailed than Great Domesday (the book we normally just call the Domesday Book).

There is also something called 'Exon Domesday' ('Exon' means Exeter in Devon). This gives more detailed information about counties in the southwest of England. This probably existed because a survey of how much tax people owed was being carried out at about the same time as the making of the Domesday Book.

All this shows how well organized the government was. This was because William had taken over a very well run country when he conquered Anglo-Saxon England. He then used this to make his own rule strong.

'How the land is settled and with what kind of people'

The Domesday Book records all kinds of information about England in 1086. It records how much tax was paid in 1066 and what the land was worth in 1086. It tells what kinds of people lived there. It says whether there were mills, how much meadow land existed from which hay could be made to feed animals, how much pasture land there was for animals to graze on, and how much woodland. Sometimes the entries include other little clues: vineyards, beehives, women making gold cloth for the king, rent paid in baskets of eels, and other glimpses into life in 1086.

A very big book

The Domesday Book is made up of 2 million words, written in Latin. It is about 900 pages long and mentions 13,418 places. It is made of vellum, a soft kind of leather and would have needed leather from about a thousand sheep. The whole book was written by one man!

Big as it is, Domesday Book is not complete. It does not include East Anglia (covered in Little Domesday). It misses out lots of northern England, London and Winchester (the two most important cities), and although it records heads of households, it misses out wives and number of children. Despite this, it includes huge amounts of information. It is now kept in the Public Records Office, in London.

The importance of the Domesday Book

The Domesday Book is important for many reasons. It tells us who the great landowners were. It tells us what kinds of people lived in the country – who was free and who was not. It records the names of places (though English names were sometimes badly written in Latin influenced by Norman French). It shows the way farming was organized. It records customs and ways of life. No other country in Europe has anything like the Domesday Book. It is unique. It is a window through which we can look at England almost a thousand years ago.

An example of Domesday Book text

What kinds of information does Domesday Book contain? Here is an example. It is the entry for the king's royal manor at Keynsham, Somerset.

'Before 1066 it paid tax for 50 hides. Land for 100 ploughs, of which 15¹/₂ hides are in lordship; 10 ploughs there; 20 slaves; 25 freedmen; 70 villagers and 40 smallholders with 63 ploughs; 6 mills worth 60 shillings; meadow, 100 acres; pasture, 100 acres; woodland, 1 league long and as wide. It pays £108; it paid £80. To this manor belongs 8 burgessses in Bath who pay 5 shillings a year.'

• A hide is about 120 acres of land.
• In lordship means everything from this land goes to support the lord.
• A freedman used to be a slave.
• A villager is a fairly well-off farmer, whose life is controlled by the lord and who has to work on the lord's land without pay.
• A smallholder farms less land than a villager.
• A league is a measurement of distance.
• Burgesses are people living in a town, who rent their house.
• The Exon Domesday adds that at Keynsham there were: '4 horses, 10 cattle, 44 pigs, 700 sheep, 70 goats'.

Questions and answers

Q1 What does Domesday Book mean?
A1 Judgement Day.

Q2 Why was it called this?
A2 People felt that it was a bit like God's last judgement day when he would decide who would go to heaven and who would go to hell.

Q3 What other names was it given?
A3 The Great Survey, The Winchester Book, The Description of England.

Q4 When was it written?
A4 It was begun in 1086.

Q5 Why was the great survey carried out?
A5 To decide who owned land and what the land was worth. Another possible reason is that William wished to improve his understanding and taxation of his royal estates and lands.

Q6 How was the survey carried out?
A6 Commissioners went out to gather information from local people. Another group of commissioners checked up on them.

Q7 Where can we find extra information not given in the Domesday Book?
A7 In Little Domesday and in the Exon Domesday.

Q8 What kinds of information can we find in Domesday Book?
A8 The names of landowners, the kinds of people living in a village, the value of a place, its resources.

Q9 Why is it so important?
A9 It tells us what life was like almost a thousand years ago.

Q10 Where is it kept now?
A10 In the Public Records Office, in London.

Check it out!

Is your town or village mentioned in the Domesday Book? Find out what the Domesday commissioners discovered about it. Who owned it? What kinds of people lived there? What were the resources? Are there any odd pieces of information? Perhaps you could design an estate agent's guide to your home area as it was in 1086!

The Microprocessor

by Brian Arnold

Introduction

Our brains continually receive small electrical signals from all parts of our bodies. These signals 'tell us' how we feel. For example, are we hot, are we cold, are we tense, are we relaxed? If our situation alters in any way then our brains receive new messages, which they process. As a result of this processing, new signals are sent out and we react to the new conditions.

Some silicon chips work in a similar way. They receive information from various sensors such as thermistors and light-dependent resistors (LDRs) in the form of small electrical currents. They process the information and then send new electric signals to deal with the situation. Chips that are capable of doing this are called microprocessors.

Control systems

One of the many applications of microprocessors is in control systems. They work so efficiently in this application that it would be difficult to find any area of our lives that is not affected by them.

In washing machines, for example, there is a chip that has been designed to receive electrical signals telling it which wash program you have selected. When switched on, it locks the door, opens valves to allow water to flow in, warms up the water to the correct temperature and turns on and off the motor that rotates the drum.

In central heating systems the signals come from the various sensors around the house. A microprocessor processes these signals and then, in accordance with the program you have selected, it will turn the boiler on and off and direct the heat to wherever it is needed.

Traditional watches are mechanical timepieces. Springs and cogs control the movements of the hands. Modern watches contain a microprocessor. Both watches tell the time but the microprocessor-controlled watch:

• is far more accurate
• is far more reliable because it contains fewer parts
• will tell us not only the time but also the day, date, and month
• can be used as a very accurate stopwatch
• will run for several years on one small battery.

As the above example shows, microprocessor-controlled systems are generally better than mechanically controlled systems in many ways.

When the first traffic lights were introduced, they operated on 'fixed timings'. For example, each set of lights would be on red for one minute and then on green for one minute, regardless of whether it was day or night, or the roads were busy or quiet. Nowadays the situation is much improved by using microprocessor control. The processor receives signals from sensors that 'tell it' if a car is approaching the lights and if the flow of traffic is heavy or light. It then alters the timing of the traffic lights in order to improve the flow of traffic.

In order to make a car more fuel-efficient, the fuel system may be controlled by a microprocessor. This receives information about the outside temperature, the engine temperature, the engine speed, and how hard the engine is being made to work, etc. It calculates the most efficient mixture of air and petrol for those conditions and then instructs the fuel injection system when it should introduce this into the cylinder. Without microprocessor control the fuel consumption would be considerably higher.

At present if you want to buy something you may need to use cash. This you can get from a 'hole in the wall' dispenser. At the heart of these dispensers are one or more microprocessors. The dispenser recognizes your own personal code or pin number, receives your request, dispenses the correct amount of money, and alters your account to include the withdrawal. However, if modern technologists have their way, soon even the cash dispenser will be obsolete because we will not be using cash. If you go to the supermarket to buy some groceries, you may see at the checkout that the cashier no longer reads the price tag stuck to the purchase. Instead he or she searches for the bar code and passes this over a small window next to the till. In doing so all the purchases are recorded and totalled, and an itemized bill is prepared for the customer's benefit. The supermarket also keeps a record of all purchases, so it can quickly assess the stock and the sales of a particular item. Before leaving the supermarket the bill must be paid. Although a small number of people still pay by cash, the vast majority of us present a plastic card to the till operator which allows the cost of our purchases to be deducted from our bank account and an equivalent amount to be added to the supermarket's account.

Questions and answers

Q1 Which part of your body behaves like a microprocessor?
A1 The brain.

Q2 Give two ways in which a microprocessor-controlled system is likely to be better than a mechanically controlled system
A2 Microprocessor-controlled systems are more accurate, more reliable, and much more versatile.

Q3 Explain in your own words why flow of traffic through a microprocessor-controlled set of traffic lights will be better than through lights that have fixed timings
A3 The microprocessor-controlled traffic lights system will sense which roads are carrying most traffic and will adjust the timings of the lights so that congestion is kept to a minimum. The fixed timings lights will not take into account changes in traffic flow, with the result that traffic may be stopped by the lights when there is no traffic entering the junction from any of the other roads.

Q4 What is a bar code? For what is it used? Find an object that has a bar code and copy this into your book. How does the use of bar codes in shops help with stock control?
A4 A bar code is a pattern of thick and thin parallel lines that indicate what an item is. This code can then be used to produce an itemized bill for a customer. Shops and supermarkets use bar codes to produce their own sales record. This in turn allows them to see the movement of stock and decide if, when, and how much merchandise needs to be replaced.

Q5 Name one device found in most homes and offices that contains at least one microprocessor (Hint: Internet)
A5 The computer.

Check it out!

Find out how a thermistor and an LDR work. In what kinds of controlled systems might they be used?

Write a brief description of how a microprocessor is made.

Look around the room in which you are sitting. Identify three objects/devices that contain a microprocessor. Explain the functions of each of these processors.

Name two control systems that use microprocessors. Describe how these control systems work.

Where is Silicon Valley? What happens there and how did it get its name?

Abracadabra – a Look at Magic Squares

by Susan Ball

In a magic square, every row, column, and main diagonal adds up to the same total. For example:

In this 3 × 3 magic square, every line totals 24.

Magic squares have been around for a long time and they were particularly popular in China around 4,000 years ago, when the Emperor Yu became fascinated by them.

Solving simple squares

Given a magic square to solve, use an already completed line to find the magic number:

Here, 3 + 5 + 7 = 15, so every line must total 15. Now it is possible to find the numbers in squares a and b. 7 + 6 = 13, so a must be 2 to make the total 15. 6 + 5 = 11, so b must be 4. In the same way we can calculate that c must be 9, d is 8, and e is 1. The completed square looks like this:

This is the basic grid.

Generating magic squares

All 3 × 3 magic squares are based on this pattern. Other squares can be formed from it by treating all the numbers in the same way, for example by adding 5 to each number, giving:

Here, the magic number is now 30.

Another, less obvious way to generate the numbers in a 3 × 3 magic square, is this method:

• take any starting number, for example 5.
• choose 2 different numbers that will be added to the starting number, for example 3 and 7.
• generate the nine numbers like this:

• put the nine numbers in order: 5, 8, 11, 12, 15, 18, 19, 22, 25
• now look again at the basic grid above and replace the numbers 1–9 in the basic grid with these numbers in order:

The magic number is now 45.

Larger magic squares

During the 15th century in Europe, magic squares of all sizes up to 9 × 9 were being constructed and investigated. The artist Dürer did a woodcut called Melancholy in which he showed the date 1514 as part of a 4 × 4 magic square, as shown here:

The magic number in this case is 34 and as well as the rows, columns, and main diagonals all totalling 34, it is also possible to find other groups of 4 symmetrically placed numbers within the square which total 34. For example, 16, 13, 4, and 1.

The numbers 1–16 can actually be used to form 880 different 4 × 4 magic squares. These may be simple, having the magic number 34 for just the rows, columns, and main diagonals, or they may be nasik containing many symmetrical properties for the same magic number.

Here are examples of each type of square:

Simple

Nasik

Construction of larger magic squares

Magic squares of even order, that is 4 × 4, 6 × 6, 8 × 8, etc, have no particular method of construction other than trial and improvement, but for squares of odd order such as 5 × 5, 7 × 7, and so on. there is a method which is demonstrated here:

• Produce a diamond shape from the 5 × 5 square.
• Number the diagonals as shown, from left to right.
• Imagine sliding the numbers from outside the square into the spaces on the opposite side of the square, keeping their arrangement.

This creates a magic square as below, which has a magic number of 65. The same method can be used for any square that has an odd order.

Magic squares are a fascinating example of how numbers can be used to mystify, entertain, and amuse. Check them out, they will keep you occupied for hours.

Questions and answers

Q1 What is a magic square?
A1 A number square in which each row, column, and main diagonal adds up to the same total.

Q2 What do we call the total for a magic square?
A2 The magic number.

Q3 Who investigated magic squares in China 4,000 years ago?
A3 Emperor Yu.

Q4 What is the magic number for a 3 #215; 3 square which uses all the numbers from 1–9?
A4 15.

Q5 To make the 3 × 3 square with a magic number of 30, what would you do to each of the numbers from 1–9?
A5 Add 5.

Q6 When constructing a new 3 × 3 square what will remain the same as in the basic square?
A6 The position of the numbers in the square in order of size.

Q7 Which 15th century artist did a woodcut that showed a magic square?
A7 Dürer.

Q8 In what year did the artist produce the woodcut?
A8 In 1514.

Q9 What is special about the type of magic square shown in the woodcut?
A9 It has extra symmetrical patterns of numbers which add up to the magic number.

Q10 What is the special name given to these more complex squares?
A10 Nasik squares.

Check it out!

(1) Find as many 4 × 4 magic squares as you can and decide whether they are simple or nasik. If they are nasik, find as many of the sets of 4 symmetrically place numbers as you can.

(2) Look at the basic magic square shown below:

It is obvious that: 4 + 9 + 2 = 8 + 1 + 6 but also: 4² + 9² + 2² = 8² + 1² + 6² and as well as: 4 + 3 + 8 = 2 + 7 + 6 we have: 4² + 3² + 8² = 2² + 7² + 6²

Investigate whether this works for other 3 × 3 magic squares. Sets of numbers like these, where not only are their sums equal, but also the sums of some other powers are equal are called multigrades. Use the library or the Internet to find out more about multigrades.

Spooky Music

by Julian McNamara

How does a composer make things go bump in the night?

The three main elements of music are rhythm, melody, and harmony. 'Easy-listening' music has a steady pulse, a good tune, and harmony that is mostly consonant (nonclashing), with occasional dissonances (clashes) that resolve correctly. It is these characteristics that make such music seem relaxing; very little comes as a surprise and everything happens as we would expect. Even a rousing march or music that makes you want to dance does not usually give you a fright.

Composers of film music often help filmmakers to create and sustain an atmosphere of tension and suspense. Composers of horror film music often tamper with, or even remove, one or more of the three basic elements of music. Sometimes a very simple change can have a very dramatic effect.

Techniques

The melodies might be very angular (disjunct) and full of awkward leaps that make it difficult or impossible to sing. Sometimes there may not be a melody at all.

The composer will carefully choose a pulse for the music that will enhance the effect of a scene. The pulse of the music affects the listener's perception of elapsed time. A slow or imperceptible pulse makes time seem to pass by slowly, and a fast pulse makes time seem to pass by quickly. At times it might not be easy to hear the pulse of the music at all, especially if the music is very slow moving. In the build-up to a dramatic climax, the pulse of the music will often start very slowly and, without the listener noticing, it will become faster and faster. It will reach its fastest point at the dramatic climax of the scene. The chords might be very dissonant (clashing), and never properly resolved.

Most of the music written from about 1600 to 1920, and most of the popular music of the 20th century, uses what is known as functional harmony. In this system two things happen. First, chords have consequences, which means that once a chord has been chosen, there is only a limited number of chords with which it can be followed. For example, chord V is usually followed either by chord I or by chord VI. Second, when a dissonant chord is used, a particular consonant (nonclashing) chord always follows it. In this way the dissonance (clash) is said to resolve. From an early age, we as listeners have learnt to expect certain chords to follow one another. The composer of film music knows that and plays with our expectations, perhaps by putting two chords together that do not really fit, or else by avoiding the resolution of dissonance.

There are some other tricks that the composer can use to help the filmmaker to create suspense through the music. Repeating patterns can be effective, especially if they get higher, faster, louder, or a combination of all three. For example, the film Jaws is all about the hunt for a shark that attacks humans. Each time the shark is about to attack, we the viewers are 'warned' by the composer. Each of the shark's attacks is signalled by a musical motif that we learn to associate with the attacks during the course of the film. The motif is made of just two notes that make a rising semitone, and it is first played very low down by the cellos and double basses of the orchestra. As the shark gets closer to its victim, the repetitions of the motif become closer together so the music seems to get faster. The repetitions also get louder, because the low strings play more loudly, and more instruments join them in playing that motif. By using the motif in this way, the composer helps to generate the tension and excitement necessary for the scene to work and be convincing.

Composers can use extremes of pitch (very high notes or very low notes), especially if, at the same time, medium range pitches are not used. From the lowest bass to the highest soprano, the human voice can cover a range of roughly four octaves. That is the equivalent of the two octaves below middle C and the two octaves above middle C on a piano. These are the pitches that humans find easiest to make with their voices and to hear with their ears. When a composer goes outside that range, listeners are taken to a place where they feel much less at home. The effect of excluding the medium-range pitches is to make the music seem much more unfamiliar and unsettling.

Using extremes of volume (very loud or very soft) is another technique, and especially by making violent contrasts between a soft passage of music, or even silence, and a sudden loud chord. This is one of the easiest ways to make you jump. So we can see that by playing with our expectations of the three main elements of music, and by using a number of other tricks, the composer of film music has an important job to do in helping the filmmaker to create and maintain an atmosphere of tension and suspense.

Questions and answers

Q1 What are the characteristics of 'easy listening' music?
A1 A steady pulse, a good melody, and functional harmony.

Q2 What is meant by 'functional harmony'?
A2 Chords have consequences, and dissonance is followed by resolution and consonance.

Q3 How can a composer of film music create tension through the use of melody?
A3 By creating a highly disjunt melody or by using no melody at all.

Q4 How can a composer of film music create tension through the use of rhythm?
A4 By playing with our sense of elapsed time, for example by using a pulse so slow as to be imperceptible, or by speeding up in the approach to a moment of dramatic climax.

Q5 How can a composer of film music create tension through the use of harmony?
A5 By using nonfunctional harmony; juxtaposing chords that do not fit; irregular resolution of dissonance.

Q6 What is a motif?
A6 A motif is a fragment of music made from a small number of notes.

Q7 How can a composer of film music use motifs to create tension?
A7 By repeating them, making them into rising sequences, and speeding them up.

Q8 What is the approximate range that the human voice can cover, from the lowest bass to the highest soprano?
A8 Four octaves.

Q9 What is a 'disjunct' melody?
A9 A disjunct melody is one which moves by leaps not steps.

Q10 Give one of the easiest ways a composer of film music can make the audience jump.
A10 By using a sudden loud chord after a passage of silence or of very soft music.

Check it out!

(1) It is really quite easy to create an eerie, spooky atmosphere using a piano. You do not even need to be a pianist! Choose two, three, or four notes at the bottom end of the keyboard, play them softly with your left hand, and hold them down. You decide whether the notes will be clustered close together, spread out, or a mixture. With your right hand play very short single notes high up on the piano. Play them at random times, with different lengths of gaps between the notes. Occasionally repeat your left-hand chord, or change it. You have now created your own instant horror film music. Try building up the tension by making a motif for the right hand and repeating it at higher pitches, at the same time getting louder and faster.

(2) Make a list of the tricks used by composers of film music to create tension. Next time you watch a television programme or film that includes an element of suspense, listen very carefully to the music to find out which tricks the composer is using to help create the atmosphere.

(3) Choose a scene from your favourite video that is full of suspense and watch it with the sound turned down. What happens? You should find that the scene seems much less scary!

Using Echoes

by Brian Arnold

When sound waves strike a hard, surface such as a wall or rock face they are reflected. This reflected sound could create an echo. Playing with echoes can be fun, such as shouting across a valley and hearing your own voice come back. There are however many situations where echoes are also extremely useful.

Echo sounding and sonar

Ships use a process called echo sounding to find the depth of the ocean beneath them. An echo-sounder emits sound waves down towards the seabed. When the waves strike the seabed, they are reflected back up to the surface. A sound detector 'listens' for the echo. The deeper the sea the longer it is before the echo is heard. Sound waves used in this way are called sonar. This stands for sound navigation and ranging. Modern sonar equipment uses very high frequency sound waves called ultrasounds. These waves have a high frequency (so high that we cannot hear them) and a very short wavelength. They can be emitted as a very narrow beam that does not spread out very much as it travels away from the source. Normal sound waves undergo diffraction and spread out a lot as they travel through the water. The echoes these waves produce are weaker than those from the ultrasounds and therefore more difficult to detect. Fishing boats often use sonar to detect shoals of fish. If the crew know the depth of the ocean below, they also know how long it should take a sound wave to travel to the seabed and return. If the wave returns more quickly than expected it is likely that the wave has been reflected from a shoal of fish swimming beneath the boat.

Modern submarines contain very sophisticated, technological equipment that permits them to remain submerged for several months. Yet they have no windows or optical devices through which they can look whilst manoeuvring through the canyons and craters at the bottom of the oceans. How is the crew able see where they are going? The answer is that they too use sonar. A submarine emits ultrasonic waves and then listens for echoes using an ultrasonic receiver. If there are no obstacles near the submarine, there will be no echoes other than those coming from the seabed below. If there are obstacles then echoes are heard. These echoes are fed into computers that warn the crew of any impending danger so that it can be circumnavigated.

Echoes in medicine

Equally exciting are the uses of echoes in medicine, for example, their use in scanning mothers to check the development and well-being of their unborn babies. Many years ago doctors would use X-rays to scan a fetus but it is now recognized that there is the possibility of the X-rays causing damage to the unborn child. This problem is avoided if ultrasonic waves are used in place of the X-rays. The ultrasonic waves emitted by a transmitter pass into the body. Where they meet a boundary between different substances – for example, the boundary between skin and bone or between bone and muscle – they are partially reflected. These echoes are detected by an ultrasonic receiver and are fed into a computer that is programmed to create an image from the signals it receives.

Echoes in industry

Echoes also have a very important role to play in heavy industry. If a large object is cast in metal, echoes can be used to check that there are no internal faults. A pulse of ultrasonic waves is passed through the object. A receiver listens for the echo of the waves from the far edge. If, however, there is a crack or flaw inside the object it prevents some of the ultrasonic waves from reaching the far edge and reflects them back to the receiver. The flaw although invisible to the naked eye is detected as an extra echo. This is an extremely important tool for checking the quality of products that are load bearing and may need to withstand high stresses, for example, the wings of an aircraft or part of the support structure of a bridge.

How animals use echoes

Although we may feel that we are a technologically advanced species, bats and dolphins have been using ultrasonic waves to locate obstacles and food for many thousands of years. Bats are so good at interpreting the echoes of the ultrasounds they emit they are able to use them to catch their prey whilst in flight.

Questions and answers

Q1 What is an echo?
A1 An echo is a reflected sound wave.

Q2 Explain what is meant by the phrase 'echo sounding'.
A2 Echo sounding is the use of sound waves to determine the depth of water under a ship.

Q3 What does the word 'sonar' stand for?
A3 Sound navigation and ranging.

Q4 What are ultrasounds? Why does modern sonar equipment use ultrasounds rather than normal sounds?
A4 Ultrasounds have a very high frequency. So high that they cannot be heard by humans. They have a very short wavelength and therefore do not spread out like normal sound waves as they travel through the water.

Q5 Explain how the crew of a fishing boat know if there is a shoal of fish swimming directly beneath them.
A5 Sound waves will be reflected from the shoal far sooner than would be expected had they been reflected from the seabed.

Q6 What does the word 'circumnavigate' mean?
A6 To sail around, to avoid.

Q7 What is a fetus?
A7 An unborn child.

Q8 What does the phrase 'the object is load bearing' mean?
A8 The object is subject to applied forces.

Check it out!

• Find out what 'radar' stands for. When do the police use radar guns and how do they work? Find out how air traffic controllers make use of echoes. Find out how radar is used with traffic lights.
• Reflected sound in a concert hall can be a nuisance. Find out what measures are taken to reduce the production of echoes here. Find out what is meant by the word 'reverberation'.
• Find out how an ultrasonic transmitter works.
• How do geologists use echo soundings to find out about rocks underground?

Smoking

by Paul Smythe

Smoking can cause a range of illnesses and diseases. Lung cancer kills one person in the UK every 14 minutes and people who smoke are 14 times more likely to die from lung cancer than those who do not. A smoking habit can cost a lot of money. In addition, smoking has some unpleasant, antisocial effects. However, the number of people – particularly young people – who smoke continues to rise.

What are cigarettes made of?

Cigarettes are made up of tobacco that when lit releases poisons that are inhaled though the mouth and go into the lungs.

Tar is an irritant that is deposited in the lungs; it is carcinogenic, which means the substances in it can cause cancer.

Carbon monoxide is a poisonous gas that is contained in tobacco smoke. It cuts down the amount of oxygen in the blood and can cause damage to the heart and arteries.

Nicotine is a drug that causes addiction; it goes into the bloodstream and travels to the brain; it causes blood pressure to rise and the heart to beat faster. The brain learns that this is normal; it learns to expect the rush that it gets from nicotine – when it does not receive it, the body will experience withdrawal symptoms.

Cigarettes also contain a number of other irritants that antagonize the cells in the body. Smoke irritates the lungs; mucus is formed to protect the cells, which causes the smoker to cough (smoker's cough).

In the first instance, smoking causes people to feel queasy and light-headed; some people cough violently as their throat and lungs are irritated by the smoke. If the person smokes more, the body learns to accept it and then worse still, learns to need it – the point of addiction.

Not surprisingly, these substances can cause serious damage to several parts of the body.

The facts

• Regular smoking may cause damage to the brain and increase the risk of a person suffering a stroke.
• Smoking causes 90% of deaths from lung cancer. The air tubes in the lungs swell because they have been irritated so much, causing bronchitis – 75% of deaths are caused by chronic bronchitis.
• Small air sacs in the lungs break down, reducing the capacity of the lungs to take in oxygen and remove carbon dioxide; this is called emphysema and leaves the sufferer unable to exercise.
• The nicotine causes the heart to work harder, putting a strain on it that may lead to a heart attack. Smoking also causes the arteries to narrow. Smokers are twice as likely to die from heart disease as nonsmokers.
• A pregnant woman who smokes passes the poisons onto her baby – this may lead to deformity, small birthweight, or even result in the baby being stillborn.
• Small arteries in the feet or legs can become blocked. If the blood cannot get through, this part of the body dies and may have to be amputated.
• Smoking also contributes to stomach disorders, and increases the risk that a person may suffer from cancer of the bladder, voice box, mouth, or throat.

In addition to the health risks, a number of unattractive physical effects are associated with smoking. The smoker's breath and his or her clothes will tend to smell of smoke. There may be a yellow nicotine stain on the fingers, nails, and teeth. Eyes may be bloodshot, skin may be wrinkled, and fur may develop on the tongue (smokers often lose a proper sense of taste) – hardly an attraction to the opposite sex!

There is also a financial cost – cigarettes are expensive, and because cigarettes are consumed regularly, they incur a regular expense that could have been spent elsewhere. If smokers were to total up how much they pay for the cigarettes they smoke during a year, they might be surprised by the results!

Smoking also has an environmental effect; woodland is destroyed, and carelessly discarded cigarettes cause half of domestic fires.

Why do people start smoking?

The consequences of smoking are taught in schools and are widely known, so why do people continue to take up smoking?

• The habit of smoking often begins in adolescence when younger people mimic their elders in order to give the impression that they are adult.
• They want to be like everyone else, and do not want to be the odd one out.
• It is believed that smoking encourages relaxation and reduces stress.
• Many young smokers believe that the health risks will not happen for a long time; they believe they will give up smoking before that happens. Sadly, they will probably be addicted by then.

'There is no such thing as passive smoking'

Passive smoking is inhaling the smoke from other people's cigarettes. It is called environmental tobacco smoke. This exhaled smoke can irritate the eyes, nose, and throat of nonsmokers. Those who are particularly sensitive, like sufferers of asthma, can have their condition antagonized. Those who live in a smoky atmosphere because they live with a heavy smoker, can actually contract serious illnesses as a result of passive smoking. In a smoky room a nonsmoker can absorb 33% of the carbon monoxide level of smokers. Children are particularly at risk.

So why do people not stop smoking?

Smoking becomes a habit. The process of lighting a cigarette, the time at which cigarettes are smoked, the situations and moods in which cigarettes are smoked, fit into a habitual pattern that is difficult to break. There is a psychological dependence, as well as a physical dependence, that is very difficult to reverse.

The National Health Service (NHS) spends £600 million a year dealing with smoke-related diseases.

The rights of smokers…

Putting it simply, many smokers argue that it is their right to smoke when and where they want. They say that they have the right to do what they want with their own bodies and nobody else has the right to tell them what to do. In addition, they point to the amount of money that smokers pay in tax, from which the country benefits.

…and nonsmokers

Many nonsmokers suggest that people should be banned from smoking in public places. Some people believe that smoking should be banned outright. They argue that nonsmokers have a right not to have their air polluted by carcinogenic fumes. They also point out that smokers cost the country a great deal of money through their use of the health service. They question whether the country should have to pay for treatment of people who knowingly put their health at risk.

Most smokers who try to give up, find quitting very difficult. Products such as nicotine patches are designed to maintain the need for nicotine but to reduce the need for cigarettes. The best way to stop smoking is not to start in the first place.

Questions and answers

Q1 How do the poisons in cigarettes affect the human body?
A1 Tar is an irritant that deposits itself on the lungs and can cause cancer. Nicotine goes into the blood and tells the brain to speed up. It is a drug and it causes addiction. Carbon monoxide reduces the oxygen in the blood, causing damage to the heart and arteries. Other irritants antagonize cells, causing excess mucus to form in the lungs, which in turn can cause illness and long-term damage.

Q2 How might a cigarette affect a person who has not smoked before?
A2 The irritation in the lungs may cause them to cough and be sick. The brain might react by giving the person a light-headed feeling.

Q3 What causes bronchitis?
A3 The air tubes in the lungs are irritated by smoke, causing them to swell.

Q4 What causes smoker's cough?
A4 The body produces extra mucus to protect the cells from irritation; this mucus causes a person to cough.

Q5 List the illnesses that can be caused to the body as a result of smoking.
A5 Heart disease; cancer of the lungs, throat, and voice box; stroke; bladder and stomach disorders; narrowing of the arteries; bronchitis; emphysema.

Q6 Describe the things you think make one person attractive to another.
A6 Personality, looks, a sense of humour… – there are many more!

Q7 Describe how regular smoking can affect a person's appearance.
A7 It stains the nails, teeth, and fingers. It can make the eyes bloodshot and the skin wrinkled. It also makes the breath, hair, and clothes smell.

Q8 Why do you think people smoke, even though many of them know the risks to health?
A8 Because they are addicted and cannot give up, because they think that the consequences will not take effect until they are much older, and because they are more concerned with creating an image by impressing friends.

Q9 What is passive smoking?
A9 Passive smoking involves inhaling other people's exhaled smoke.

Q10 Describe the opposing views concerning the rights of smokers and nonsmokers.
A10 Smokers argue that they have a right to do what they want with their bodies. They also point out that smokers contribute to the wealth of the country by paying a high tax on cigarettes. Nonsmokers suggest that smokers pollute everyone's air, they also criticize the cost to the health service. They feel that smokers should not take up hospital beds that should belong to those people who did not knowingly involve themselves in activities dangerous to their health.

Check it out!

Choose one risk to health caused by smoking and use the Internet to find out more about it.

Basic Hindu Beliefs

by Glennis Atkinson

Background

It is held that there are certain basic ideas that are accepted by all Hindus.

• The acceptance that a soul (atman) is born many times on earth. Samsara is the world, the place where the soul's passage occurs through a series of lives in different species. This is known as transmigration of the soul. The body grows old and dies but the soul is reborn in another body.
• The body that the soul is reborn into depends upon actions in the previous life. Good deeds lead to a better rebirth; bad deeds lead to a worse rebirth. This is the law of cause and effect, known as karma.
• The aim of Hindus is to break free from the cycle of birth, death, and rebirth and to gain release of moksha.
• The spiritual knowledge, which leads to freedom, can be gained through yoga and meditation, or devotion, or through good works. Those who love God completely can find freedom. Likewise those who serve fellow human beings without looking for gain develop in the spiritual knowledge that brings release.

Samsara

Hindus believe that each individual has a soul (atman). The soul is the real self and cannot die.

Hindus believe that a person's physical body returns to dust. At death, Hindus cremate the deceased. Cremation is important because it ensures that the body returns to the elements in the form of ashes. The fire releases the soul to return to the earth. The atman of the person lives and transmigrates: it goes on to be reborn in another body, unless it attains moksha (release).

The constant cycle of birth and rebirth is called samsara.

Karma

Karma is the law of cause and effect, which determines the rebirth of the soul. Hindus believe that one lifetime is not enough to work out a person's destiny. The soul transmigrates into different bodies. The new rebirths are determined by a person's karma. This law maintains that a person's position in life is according to how good they were in the previous life. Karma is a moral or behavioural law and works because people are aware of their actions in a moral sense. They know the difference between right and wrong, good and bad.

A person's present condition, status, and happiness are directly related to the previous life. If a person had lived a morally and spiritually good life, then the soul would be reborn into a better life. A bad life would lead to a worse rebirth. This indicates that human beings are wholly responsible for their present condition and future. No god fixes the future for humans; the law of karma is automatic.

Relatives of deceased Hindus try to scatter their ashes on the River Ganges in India. This is thought of as a sacred river and it is said that the holy waters can remove bad karma and help the soul attain moksha.

Moksha

Moksha is the ultimate liberation from the process of transmigration. When a soul attains this state, it is released from the cycle of birth, death, and rebirth. For Hindus, the ultimate aim is to break away from the cycle of birth and rebirth so that their soul can be with united with Brahman (the Ultimate Reality or World Soul) forever.

Release happens when a person manages to live a life free from selfish desires, hatred, greed, and envy. The life must also be free from the material considerations of the world. Only then can a person achieve moksha, and be free from samsara.

The paths to moksha can be achieved in three ways:

• Jnana-yoga means the path of knowledge that aims at the liberation of the soul. This involves meditation, as in that way it is possible to know the truth and be released from attachments of this world. For those who practice jnana-yoga, the result will be release from karma and attainment of moksha.
• Karma-yoga is the path of self-realization. This is achieved by dedicating the fruits of one's work to God. By living free from the desire for material or selfish gain a person can be regarded as on the path to moksha.
• Bhakti-yoga is the path of loving devotion. This is the path followed by most Hindus. It is aimed at developing a pure love of God. It is achieved through daily worship (puja), in prayer, and in offerings. This path is God-centred; a person's actions are performed for God and not for the self.

Ahimsa

Ahimsa is also an important concept for Hindus seeking moksha. It refers to respect for life. It is sometimes translated as nonviolence, but it is much more than that. It involves having an attitude of love and humility towards all other beings. This idea of respect for all life is central to Hinduism, with its belief that Brahman is in all things, animals as well as people. Those who hurt others will build up bad karma, which will hinder moksha. Devout Hindus try to avoid causing any sort of harm in the world.

Questions and answers

Q1 What is meant by atman?
A1 The atman is the term used to refer to the real self or the soul.

Q2 What do you understand by moksha?
A2 Moksha is liberation from the cycle of birth, death, and rebirth.

Q3 Research the Bhagavad Gita. What is it?
A3 The Bhagavad Gita is the most important scripture for most Hindus. Tradition dates it back to 3,000 years BC. It is considered a sacred text (Upanishad). It is known as the Song of the Lord. The major message of the Bhagavad Gita is that devotion to God is the highest form of worship. Everything anyone does, if it is done with love, is acceptable to God.

Q4 What do Hindus mean by samsara and karma?
A4 Samsara is the endless cycle of birth, death, and rebirth. The cycle has no beginning and no end. The soul is the real self and cannot die. The atman (soul) of the person lives and transmigrates: it goes on to be reborn in another body, unless it attains moksha. Karma is the law of cause and effect that determines a person's rebirth. It is automatic. A person's present condition, status, and happiness are directly related to the previous life. If a person had lived a morally and spiritually good life, then the soul would be reborn into a better life. A bad life would lead to a worse rebirth. The aim of Hindus is to break free from the cycle of birth, death, and rebirth and to gain the release of moksha.

Q5 Explain what Hindus mean by moksha.
A5 Moksha is the ultimate liberation from the continuous cycle of death and rebirth. For Hindus, the ultimate aim is to break away from the cycle of birth and rebirth so that their soul can be united with Brahman (the Ultimate Reality or World Soul) forever. Moksha can only happen when a person manages to live a life free from selfish desires, hatred, greed, and envy.

Q6 What is karma-yoga?
A6 Karma-yoga is believed to be one of the paths to moksha. It is the path of self-realization, which is achieved by dedicating the fruits of one's work to God. A person must live free from the desire for material or selfish gain.

Q7 Find out why the River Ganges is considered important to Hindus.
A7 The River Ganges is sacred because the goddess Ganga descended to Earth and the locks of Shiva's hair broke her fall. This divided Ganga into seven streams. The waters of the Ganges are believed to liberate the atman (soul). People wash in the river in the belief that their s