The New Children's Encyclopedia

Colonial America

HISTORY AND POLITICS By the early 1600s, more and more Europeans
were sailing across the Atlantic Ocean to establish
colonies in the eastern areas of North America.

Over the next 170 years these colonies grew.

Reconstruction TELL ME MORE... POCAHONTAS
of the Mayflower As a young girl,
In November, 1620, a group Pocahontas helped to
of Pilgrims from England on make peace between the
board the Mayflower arrived Jamestown settlers and her
in North America after a Native-American tribe.
grueling 66-day journey.
They founded Plymouth
in Massachussetts.

The Plymouth settlers

The Mayflower pilgrims had come

to the “New World” so they could

worship freely without 7/7
persecution. Their new
life was tough and half

of the group died from The Thanksgiving festival now
disease or starvation celebrated in November in the
during the first winter. United States has its origins in the first
However, most of the Thanksgiving feast held in the fall of
local Native Americans 1621 by the Pilgrims and Native
were welcoming and Americans to celebrate their first
showed them suitable
crops to grow. good harvest.

TIMELINE OF COLONIAL AMERICA 1608 1620

1607 Quebec City is The Mayflower pilgrims
founded by the establish a settlement at
The Jamestown settlement in Virginia French along Plymouth, Massachusetts.
was the first permanent the Saint
English settlement in Lawrence River.
North America.

200

Europe MS COLONIAL AMERICA
North
America Atlantic The original 13 colonies

ocean Other British territories

The British colonies By 1733, NH MS Massachussetts
there were 13 colonies loyal to NH New Hampshire
Britain along the east coast of NY MS RI Rhode Island HISTORY AND POLITICS
North America. In 1763, the CN RI CN Conneticut
French surrendered their land to NY New York
the British. In the 1760s, Britain PA NJ NJ New Jersey
began to tax the American PA Pennsylvania
colonists, but their authority MD DEL MD Maryland
over the New World was starting DEL Delaware
to weaken, since the colonists no VA VA Virginia
longer needed their protection. NC North Carolina
North NC SC South Carolina
America GA Georgia
SC

GA Atlantic
ocean

DECLARATION On July 4, 1776, the
Continental Congress of the American colonies
issued a Declaration of Independence, signed
by representatives of all 13 colonies. The united
colonies were free, independent states.

TAKE A PICTURE

The historic area of Williamsburg, which
became Virginia’s capital in 1698, has been
restored and re-creates colonial times.

Revolutionary War In the 1770s, the
American colonists began to rebel against
British rule and were especially angered by

the heavy tax on tea in 1773. Between
1775 and 1783, the colonists fought the
British army and won. The British were
forced to recognize their new independent
country—the United States of America.

1663 1763 1773 17751783

Companies were The French The Boston Tea Party The Revolutionary War was
established to trade surrendered their was a protest by when the 13 colonies rebelled
goods, such as fur colonies to Britain, some American against the
skins and tobacco, expanding the area colonists angered British and won
with Europe. the British by their high taxes independence.
controlled. paid to the British.
201

HISTORY AND POLITICS BROOKS SLAVE SHIP This ship The slave trade
was designed to carry around 450
slaves, but more than 600 were often Slavery has been a feature of many societies, such as
packed in, chained together. ancient Egypt and Rome. But it was the Atlantic slave
trade that made slavery a worldwide issue. It had its
roots in the Portuguese transportation of workers from
Africa to Madeira, in 1470. By the time slavery was
abolished 400 years later, around 12 million slaves
had been taken from Africa to the New World.

North America 3 Europe

Sugar Guns
cane
Wine
Cotton
Africa
Coffee

Atlantic 1
Ocean

Caribbean Sea 2

Slaves

South America

THE TRIANGULAR TRADE 1 EUROPE TO 2 AFRICA TO 3 AMERICAS TO
The slave trade was all about money. European
traders exported goods to Africa, then used the AFRICA The AMERICAS Called EUROPE Sugar,
ships to pick up a new cargo: people. They were Europeans traded “The Middle Passage,” rice, cotton, coffee,
taken to work on plantations in southern North copper, iron, cloth, people were snatched tobacco, and rum
America, South America, and Caribbean islands. wine, glassware, and from villages and fields from the plantations
guns with African and marched to the were brought back
202 landlords for people. coast to slave ships. to Europe.

THE SLAVE TRADE

An ankle fetter

SLAVES FOR SALE HISTORY AND POLITICS
On arrival in the New World, slaves were
taken to markets, where they were sold by
auction to plantation owners. The slaves
were branded—burned with hot
irons—with the mark of their new
owner. Men, women, boys, and girls
were all put up for sale.

NO ESCAPE From the moment
they were first seized in Africa, slaves
were forced to wear shackles such as
neck collars and ankle fetters. They
were chained together so that they
could not escape.

HISTORY AND POLITICS The age of empire UnitedStates

Since the 1600s, European countries had steadily gained land and
influence over countries around the world. From the mid-1800s,
they competed against each other to control new trade markets,

increasing the size of their empires and becoming wealthy.

North America IMPORTS AND EXPORTS
Many people from European countries imported raw materials
Europe immigrated from their empires and exported manufactured
to the United States goods back to their colonies.
or Canada to escape
bad conditions at Europe
home, such as the potato
famine in Ireland. The North RAILROADS Africa
arrival of these new settlers America A vast network of tracks
led to the exploration of were laid across countries
remote inland areas and Coffee and continents for the
a route across the whole transporting of goods
continent. by rail.

TELL ME MORE... Sugar Gold
cane
In 1805, Meriwether Lewis and William
Clark were the first American explorers South
to find a route through the Rocky America
Mountains to reach the western
territories of America. Other explorers,
traders, and settlers followed afterward.

Cocoa

SOUTH AMERICA SOUTH AFRICA The
During the 1800s, many discovery of diamonds in
of the countries in South the mid-1800s transformed
America became a poor colony into a much
independent. Only the desired one and sparked
British, French, and conflicts in the area.
Dutch had colonies with
big plantations.

BOER WAR In 1899, Africa
war in the south of Africa The “scramble for Africa” began in the
broke out between the Dutch 1870s, when European countries
settlers, known as Boers, and competed against each other to gain
the British, seeking control of control of land on this continent. Explorers
the mineral-rich land. had found raw materials such as gold and
diamonds, and there was land and people
204 available for setting up plantations.

Russia THE AGE OF EMPIRE

China Empire-builders INDEPENDENCE
The main European colonial
powers were Great Britain, France, The Commonwealth Games HISTORY AND POLITICS
the Netherlands, and Portugal.
By the end of the 19th century, After World War II, many
Great Britain’s empire covered colonies started campaigning to
one-quarter of Earth’s land surface. become independent countries.
During the 1940s through 1960s,
This map Britain Italy most gained independence,
shows the France Netherlands although the transition for some
borders and Spain Germany countries, such as India, caused
empires in Portugal Ottoman Empire violence. Many nations still have
1900. links to their colonial power. The
Commonwealth is an organization
EGYPT TAKE A LOOK: TRADE of 53 countries that were once
The Suez Canal, opened part of the British Empire.
in 1869, allowed an Access to raw materials was very
easier and quicker access important to the growing industrial
route to India. countries. It was simpler and
more profitable to own the
Suez Canal Tea country where these came
from rather than negotiate
India with the local rulers. Colonies
also provided
cheap labor
for the mines
and the
plantations. Cotton Rubber

Ivory MALAYSIA

The British

government set up

very profitable tin

mines and rubber

plantations. Gold India
By 1900, Britain ruled the whole of
Gold Australia India. Many British administrators and
traders lived there with their families,
INDONESIA AUSTRALIA enjoying a privileged colonial lifestyle.
After the success of the Dutch East The discovery of gold in the town Owners of tea plantations became rich,
India Trading Company in the of Victoria in the 1850s led to a while the local workers lived in poverty.
17th and 18th century, the Dutch gold rush. The European
government took control and set population grew very quickly.

HISTORY AND POLITICS Industrial Revolution

Between 1750 and 1850, the development of
power-driven machines transformed the lives of
people, first in Britain and then other European
countries and the United States. This period is
known as the Industrial Revolution.

Burning the coal to produce
steam to power the machines
produced choking smoke.

Child labor Children as young
as six years old worked

in the factories, until 1833,
when under-nines were banned.

They worked up to 12 to 14
hours a day with few breaks.
Sometimes, they were injured or
even killed by the machinery.

7/7 FACTORIES From the
1790s, steam power replaced
Before the Industrial Revolution, the previously water-powered
most people worked as farmers in machines. Inside the factories,
the fields. Spinning and weaving were the noise of the machines was
deafening. Outside, the towns
done at home. The invention of were dirty and unhealthy places.
machines changed this. Thousands of
workers seeking more pay moved into 1779
the towns to work in the newly built
Samuel Crompton’s water-
factories that housed these powered, spinning “mule”
big machines. was bought by
many factory
TIMELINE OF INDUSTRIAL INVENTIONS owners.

1712 1764

Thomas Newcomen built James Hargreaves invented the
the first commercially spinning jenny—
successful steam a mechanized
engine. It was used spinning wheel
to pump water out that could spin
of mines. eight threads at once.

206

INDUSTRIAL REVOLUTION HISTORY AND POLITICS

TELL ME MORE...

The Industrial Revolution caused
much unrest. Skilled textiles workers,
in particular, were angered by the
introduction of looms that could be
worked by unskilled workers making
low wages, forcing them out of work.
One group, known as the Luddites,
destroyed the machines in cotton and
woolen mills.

Cotton gin The US became the WHO’S WHO?
world’s leading cotton producer,
thanks to the invention of the cotton O James Watt (1736-1819) A Scottish
gin by Eli Whitney. This machine engineer who made improvements to the
could quickly separate the cotton steam engine in 1769 so that machines
fibers from the seeds, which had could be powered without water.
previously taken ages to do by hand. O Eli Whitney (1765-1825) An American
inventor who designed the cotton gin
TAKE A PICTURE while staying on a plantation in the
Southern states.
Canals were built to transport the heavy loads O Francis Cabot Lowell (1775-1817)
to and from the factories. The boat lifts on the An American merchant who established
Canal du Centre, Wallonia, in Belgium, show the first textile mill in the United States.
the amazing engineering feats of this age. O George Stephenson (1781-1848)
An English engineer who built the first
public railroad line in the world.
O Isambard Kingdom Brunel (1806-
1859) A British engineer who designed
many tunnels, bridges, railroad lines,
and ships.

Railroad mania In 1804,
Richard Trevithick added
wheels to his steam engine
so that it could run along

tracks. Within thirty years, a
network of railroads for

transporting raw materials,
goods, and people by steam
locomotives was constructed.

Traveling around was now
much quicker.

1785 1793 1801 1830

Textile-making could be done Cotton could be Joseph-Marie Jacquard’s The world’s first all-steam
much faster by Edmund produced much loom was the first passenger railroad opened in
Cartwright’s faster with Eli Britain.
power loom. Whitney’s machine to be controlled by
cotton gin. punched cards— 207
an idea later used
in computing.

World War I WHO’S WHO?

At the beginning of the 1900s, military and O Two main groups battled each other—
political tensions existed between some of the the Allies led by the British, French, and
countries of Europe. The assassination of the heir Russian armies, and the Central Powers
to the throne of Austria-Hungary was the spark led by the German, Austro-Hungarian, and
needed to fire up a war that involved the world. Turkish armies.
HISTORY AND POLITICS O The British and French armies included
many recruits from their colonies and
Portugal territories around the world.
Tunisia O In total, nearly 30 countries were drawn
in to take part in the fighting.
O The US joined the war in 1917.

MILITARY TRANSPORTATION Atlantic Ocean

O Aircraft: Biplanes and triplanes were Great Britain Russia
used to fly over enemy lines to observe
their movements and take photographs. JUTLAND
O Vehicles: Horse-drawn vehicles were
gradually replaced by mechanical ones Western Germany
to transport men and supplies to and Front
from the front line.
O Tanks: The first tanks used in 1916 VERDUN Austria-Hungary
were not very reliable, but a year later
they were leading the way across to the France Italy Romania Black Sea
enemy trenches, shielding the troops.
O Warships: Fleets of warships were Serbia
used to protect supply ships from Bulgaria Turkey
attacks by the German U-boats. Greece
GALLIPOLI (The Ottoman
German
triplane Empire)

Morocco Mediterranean Sea
Egypt
Horse-drawn Algeria
ambulance

Libya

Allied powers World at war Although most of the
Central powers fighting took place in Europe, there was
Neutral nations also fighting in the Middle East, in
Key battle sites Africa, and in the German colonies in
China and the Pacific Ocean.

TIMELINE OF WORLD WAR I 1915

1914 The German’s
zeppelins made
The assassination of Archduke Francis frequent nighttime
Ferdinand on June 28, 1914, caused bombing raids over
Austria-Hungary to declare war on Serbia. British cities.
European countries took sides, and by
August The Great War had begun.

208

THE FRONT LINE CROSSING WORLD WAR I
By the end of 1914, a network of NOMAN’S LAND
trenches zigzagged from the Belgian Most attempts to Gas attack
coast to the Swiss border, forming advance occurred A deadly chlorine
at dawn or dusk.
gas was used for
the Western Front. From these the first time in HISTORY AND POLITICS
the battle for the
positions, the Allied troops tried to
Belgium town
push back the advancing German of Ypres in 1915.

army, but neither side made much

progress. Under fire from machine

guns, the strip of land between

each other’s trenches was

impossible to cross.

Trenchcoat

TAKE A PICTURE

More than half of the 65 million men who
fought in the war were killed or injured and
about 6.6 million civilians also died.

1916 1917 1918

The naval The US joined the Allies, At 11 a.m. on the 11th
battle of Jutland angered by the German day of the 11th month
was the largest U-boat attacks on (November), an armistice
fought in history. shipping in the (cease fire) took place. A peace
Atlantic Ocean. treaty was later signed.

209

HISTORY AND POLITICS TELL ME MORE... World War II
The Nazi party, led by Adolf Hitler,
was voted into power in 1933. Hitler The peace treaty signed at the end of World War I
promised the German people an end (the Treaty of Versailles in 1919) forced Germany to
to unemployment and hardship and give up much of its land and wealth and restricted
wanted to restore the country’s pride the size of its army. Twenty years later, the Nazi
and military strength. Party in Germany had rebuilt the nation, and their
leader, Adolf Hitler, was determined to rule Europe.
Adolf Hitler
Destruction Bombing raids by the Allied and
Axis powers caused huge destruction across

Europe, the USSR, and east Asia. The raids were
intended to target strategic buildings, such as
airfields, factories, ports, and railroads, but
often homes were destroyed, killing civilians
or forcing them to evacuate (leave the area).

Adolf Hitler (1889-1945) Born in
Austria, Hitler became an influential
politician in Germany. After being
appointed chancellor in 1933, Hitler
created a one-party state and made
himself an all-powerful dictator.

FAST FACTS

O The leaders of Britain (Winston GAS MASK Countries
Churchill), the Soviet Union (Josef Stalin), feared that gas would be used
and the US (Franklin Roosevelt) met twice by the enemy so many people
during the war to discuss strategies. were issued with gas masks.
O Resistant groups of people from They were never needed.
German-occupied countries helped the
Allies by spying and acts of sabotage.

TIMELINE OF WORLD WAR II

1939 1940 1941 1942

On September 1, Between June and October 1940, On December 7, Japan In August, the Germans began
German forces the German air force battled the attacked the US naval the six-month-long battle for
invaded Poland. British air force in the skies base at Pearl Harbor Stalingrad in the Soviet Union.
Britain and above Britain. in Hawaii. The US
France declared entered the war.
war on Germany.

210

WORLD WAR II

THE WORLD AT WAR

Britain Soviet Union
Germany
United States HISTORY AND POLITICSJapan
of America Atlantic THE COLD WAR
(US) Ocean Pacific
Ocean
Pacific
Ocean

Allied powers (dots show Indian
countries annexed by the USSR) Ocean

Countries that joined the Allies
after the Pearl Harbor attack
Axis powers (dots show countries
that were conquered by them)

Neutral countries

World at war Until mid-1941, the two BATTLE OF STALINGRAD PEARL HARBOR
sides were the Axis (Germany, Italy, and The unexpected attack
some east European countries) and the BRITAIN After Germany invaded the by the Japanese air force on
Allies (Britain, France, and countries in the US naval base in Hawaii
their empires). Nations around the world conquering France in June Soviet Union in 1941. There destroyed 19 ships and killed
became involved when Germany invaded 2,403 soldiers. The United
the Soviet Union and Japan’s attacks began. 1940, Germany planned to was a huge loss of life on both States immediately declared
war on the Axis powers.
take over Britain. The British sides, especially in the battle

air force was targeted first, for Stalingrad in the south.

but the German air force In 1943, the weakened

was unable to defeat it. German army surrendered.

THE CAMPS
Auschwitz in
Poland was
one of eight
concentration
camps that had
gas chambers.

The Holocaust The Nazi party was TAKE A PICTURE
very anti-Semitic (against Jews). They
forced Jews to wear badges with a After the war, relations between the Soviet
yellow star and, from 1942, sent Union and the US became very tense. Eastern
them to concentration camps. Many and western Europe were separated. The
millions of Jews died from illness, collapse of the Berlin Wall, Germany, in 1989
starvation, and in gas chambers. became a symbolic end to this Cold War.

1943 1944 1945

In May, the On June 6 (D-day), In May, Germany
Axis army in Allied forces invaded surrendered, but the war
North Africa the beaches of continued in east Asia. Japan
finally surrendered Normandy, France, surrendered only after atomic
to the Allies. and began to push bombs were dropped on two
back the Axis forces.
cities in August.

211

HISTORY AND POLITICS Revolution! The Year of Revolution A wave of In March,
unrest spread across many European a peaceful
World history has been marked countries in 1848. With many starving demonstration
by episodes when a sudden uprising and unemployed, the demonstrators in Vienna,
of people driven by hardship has wanted more rights and a greater say Austria,
overthrown those in power. An in how their countries were governed. turned violent.
alternative political system has been Although the revolts fizzled out, they
established in the hope for a better life. were the sparks for later political reforms.

REVOLUTIONARY LEADERS

O Vladimir Lenin (1870-1924) was leader of the Bolshevik Social
Democratic Workers’ party and first head of the Soviet state.
O Mohandas Ghandi (1869-1958) is considered the father of India.
O Mao Zedong (1893-1976) was a Chinese communist leader and
the founder of the People’s Republic of China.
O Fidel Castro (1926- ) has been president of Cuba since 1949
and is the world’s longest serving leader.

1789 “LIBERTY, EQUALITY, FRATERNITY!” 1799 “WORKERS OF ALL 1848
Despite France facing severe food and money LANDS, UNITE!”
shortages, King Louis XVI and his wife Queen In 1848, a German political
Marie-Antoinette enjoyed a luxurious lifestyle. writer, Karl Marx, published
his thoughts on communism.

The storming of the Bastille LOUIS XVI Napoleon The French Revolution
On July 14, 1789, the starving Executed in 1793 wrote about After the death of Louis XVI,
people of Paris rioted when they 33,000 letters. the country became a republic,
heard rumors that King Louis but there was a reign of terror,
XVI had ordered the army to with thousands of people executed
suppress the commoners and at the guillotine. In 1799, the
wanted to raise taxes. army eventually gained control
under the dictatorship of its
general, Napoleon Bonaparte.

NAPOLEONIC
WARS Napoleon
crowned himself
emperor of the First
French Empire in 1804
and led successful
military campaigns
across Europe.

212

India’s peaceful revolution The political REVOLUTION!

figure Mohandas Ghandi returned to Cuban revolution The revolutionary Fidel
Castro led a small band of rebels and peasants in
India in 1914. He began a gradual The Indian spritual their two-year fight against the large army of the HISTORY AND POLITICS
campaign of urging Indians to boycott and political leader, dictator Fulgencio Batista. When Castro took
the British-run courts and schools and Mohandas Ghandi, power in January, 1959, he made many reforms,
resign from government positions. In in 1947—the year improving Cubans’ healthcare and education.
1930, Ghandi led a 240 mile (386 km) India finally won
independence from Che Guevara was one
of Castro’s rebel group
march protesting against the tax on salt. the British. leaders.

Fidel Castro

1914-47 “BE THE CHANGE 1917 “SMASH THE OLD
YOU WANT TO SEE WORLD, ESTABLISH
IN THE WORLD.”
Ghandi encouraged 1956-58 1966-76A NEW WORLD.”
resistance through non- Young people in China
violent civil disobedience. formed the Red Guards
to promote Mao’s message.

China’s cultural revolution In 1966, Everyone had to read
the leader of the Chinese Communist and carry around a
Party, Mao Zedong, launched a
campaign to make China a classless copy of Mao’s “Little
society. Millions of educated and Red Book.”
privileged people were forced into
manual labor to be “reeducated”
and many thousands were killed.

Chairman Mao reimposed his control

Workers and mutinied soldiers marched
on the streets of Petrograd (St. Petersburg).

The two revolutions Stirred up

by the Bolshevik socialist party,

the starving and war-weary Russians HAMMER AND

demonstrated against the unpopular SICKLE BADGE
Czar (king) Nicholas II in February, In 1922, Russia was
renamed the Union of
1917, who then abdicated. In Soviet Socialist Republics
October, led by Vladimir Lenin, the (USSR). Their symbol

Bolsheviks overthrew the government represented the unity of

to form the first communist state. the workers and peasants. 213

HISTORY AND POLITICS In the news FAST FACTS

Every day, history is being made. Events affecting ■ On September 11, 2001, terrorists
people’s lives and altering the politics of nations linked with a group called Al-Qaeda
around the world are reported in the newspapers, attacked buildings in the United States.
or on the television and the Internet. These 9/11 attacks have led to a “War on
Terror” against Muslim militants.
■ Founded in 1945, the United Nations is
an international organization that seeks
to achieve world peace.

BREAKUP OF THE USSR CONFLICT IN AFGHANISTAN

In 1991, the The Taliban is an Islamic movement that
Union of Soviet ruled Afghanistan from 1996-2001. After
Socialist Republics the 9/11 attacks (see Fast Facts), Al-Qaeda
leaders were believed to be sheltering in
(USSR) was broken Afghanistan and this led to the country being
up and some areas became attacked by the United States and its allies.
independent countries. They overthrew the Taliban government,
Since then, other areas have but Taliban troops have continued to fight
wanted independence, against the new government of Afghanistan
sometimes causing unrest. and against the US and allied troops that are
still stationed there.
u CHECHNYA JOBS PROTEST In 2008, people protested
Over 90 per cent of the during the conflict between Russia and u GULF OIL FIELD
population of Chechnya the independent state of Georgia. The states around the Gulf have
are unemployed. The become super rich due to the oil
dangerous work of Russia, or the Russian Federation, revenue. The 300-mile (483-km)
climbing on to unstable became the largest of the new long oil field in Saudi Arabia is the
ruins to collect construction world’s largest.
material is one of the few countries, continuing as a
ways to make some money. communist state. Rebel fighters
from the Chechen Republic, or
Chechnya, have taken
hostages in an attempt to
get independence from
Russia. In 2008, Russia
and Georgia were
fighting over the control
of the areas of Abkhazia
and South Ossetia.

IN THE NEWS

ISRAEL AND PALESTINE

After World War II, the state The West Bank and the
of Israel was created as a
home for Jewish people. The Gaza Strip are the two
Palestinians also have claims
to the land. Since then there unconnected regions of
have been wars between Israel and its
Arab neighbors and in more recent years, the Palestinian territories.
many suicide bombings and other
attacks between Israel and Palestinians. A network of fences, HISTORY AND POLITICS

trenches, and high

concrete walls have been

constructed as a barrier u BREACHING THE WALLS
around the West Bank The Palestinians in the Gaza Strip have
and the Gaza Strip. made a number of attempts to cross into

Egypt, seeking food and supplies.

THE GULF REGION CENTRAL AND EAST AFRICA

The region around the Persian Gulf—a Fighting between rebel groups
large bay that extends from the Indian and government forces in some
Ocean—is the world’s largest source of countries in central and east
crude oil. Any conflict in the region is an Africa have forced many
immediate threat to oil supplies around the world. thousands of refugees to flee their
Other countries are quick to intervene to homes. The area is also prone to
safeguard the stability of the region
and their own oil supplies. environmental disasters, such as
droughts or floods, causing
food and water shortages.

Refugees living in
vast camps rely on
food aid supplied
by charitable
organizations.

The 2003 Gulf War Coalition
In 2003, the world was concerned that troops continued
Iraq might be making dangerous to be stationed in
biological and chemical weapons. A Iraq to support the
US-led multinational force rapidly democratic process
defeated the Iraqi army and the and the rebuilding
authoritarian president was replaced of the country.
by a new elected government.

TAKE A PICTURE

The United Nations (UN) organization aims to
develop friendly relations between the countries
of the world, bringing them together to solve
international economic, social, cultural, and
humanitarian problems.

What is a government?

HISTORY AND POLITICS A government is a small group of people who make laws and decisions about
how their country is run. They raise money from everyone in taxes and decide
how this money is to be spent, such as on hospitals, schools, the army, prisons,
and the building of new roads.

ONE-PARTY STATE WHO’S WHO?

In some countries, only REPUBLIC O President A head of state of a republic
one political party is OF CUBA with either extensive powers (as in the
allowed to exist; all others The Cuban US) or limited powers (as in Germany).
are banned. When there Communist O Prime minister The head of
is an election, the one Party is the government in a parliamentary democracy.
party decides who the only recognized O Dictator A ruler who has absolute
candidates will be and political party. power.
the voters only get to O Monarchy The hereditary rule of a
approve that choice. single person. An absolute monarch has
unchecked powers, while a constitutional
MONARCHY monarch has limited powers.
O Opposition The parties that are not in
Many countries, like the UK, a government and may disagree with the
governing party.
have a king or queen who acts O Senate The upper house of a
legislative assembly (as in the US).
as head of state but does not O Cabinet A group of ministers or others
that advises a head of government.
govern the country. However, O Representative A person who is
elected to represent the public in
there are a few countries where the monarch still KINGDOM OF making laws.
holds all the power and governs the country. These BRUNEI
“absolute monarchs” are not elected, but when The Sultan of Brunei has
they die, power passes to their son or daughter. absolute power.

MILITARY RULE

In some countries, if the

WHAT IS A GOVERNMENT?

MULTIPARTY DEMOCRACY

TAKE A LOOK: VOTING IN ELECTIONS

In a democracy, all adults are allowed to HISTORY AND POLITICS

THE CANDIDATES vote. On election day, they are given a
In an election, candidates may be piece of paper with the names of the
nominated by different political parties. candidates on it. They vote by putting a
The person who gets the most votes is cross or a number next to the candidate’s
elected and the party with the most elected name. The voters deposit their voting slips
into a locked ballot box. The votes are
candidates forms the government. counted and the candidate with the most

SYSTEMS OF votes is elected to the position.

GOVERNMENT TYPES OF DEMOCRATIC GOVERNMENTS:
A constitution is a written

document or unwritten UNITED KINGDOM (UK) CONSTITUTIONAL MONARCHY
code that establishes the

structure and rules of the

political organization of a

country. Constitutional

democracies may take the Parliament
form of republics, as in
France and the US, or House of Commons House of Lords
constitutional monarchy, as
in the UK and Spain. The Governing Party: Opposition Parties: Senior Unelected Senior
country may have a bishops Lay peers judges
presidential system (US), Prime Minister Opposition Leaders

Cabinet Shadow Cabinets

a parliamentary system Members of parliament Opposition MPs

(UK), or a semipresidential

system (France). UNITED KINGDOM UK The monarch acts as head of state, but the parliament is responsible
for making and changing the laws in the UK, which is done with the majority approval of both the

PROTESTS House of Commons and the House of Lords.

If people disagree with a bill, UNITED STATES OF AMERICA (US) CONSTITUTION
they will often organize protests

to try to make their government

take notice or change it.

Executive Branch Legislative Branch Judicial Branch
The White House The US Capitol Supreme Court and
other courts of law
President Congress

Vice President Senate House of Representatives

Cabinet Elected Senators Elected Representatives

UNITED STATES OF AMERICA US The United States is the oldest constitutional republic
and has three separate branches. The executive branch carries out the instructions of Congress, the
legislative branch creates and changes laws, and the judicial branch manages the system of justice.

DEMOCRATIC 217

SCIENCE SCIENCE

The word science comes from the Latin scientia, meaning knowledge.
Scientific ideas were recorded by the philosopher Aristotle about 2,350 years ago.
Sound waves with a frequency of 20,000 Hz or more are known as ultrasound.
The universe is about 13.7 billion years old and is expanding at an increasing rate.
The Earth’s core is a solid iron sphere surrounded by a deep layer of molten iron.

How What is
does a terminal
nutcracker crush a velocity and how
walnut? Find out does it affect a
on page 233 skydiver? Find out
on pages 234—235
218

Definition: Science helps us SCIENCE

understand the workings of
the universe and everything in
it. We increase our knowledge
by observing, experimenting,
and testing theories.

Einstein’s famous equation E=mc2 explains that energy and matter are the same thing.
The Earth’s climate is changing as a result of carbon dioxide produced by human activity.
The instructions to make you are carried on about 25,000 genes in the DNA of your cells.
In 1514 Copernicus was the first to show that the Earth moves around the Sun.
Sound travels at a speed of 740 mph (1,190 km/h) through dry air that is 32°F (0°C).

Why do How do we get
objects electricity from
sitting in water solar panels? Find out
seem distorted on page 231
at the surface?
Find out on page 241

SCIENCE What is science? TAKE A LOOK:
COPERNICUS
Science is the search for knowledge about the world
and the way it works. Unlike other ways of explaining O One of the greatest ever scientific
how the world works, science is based on experiments theories was put forward by Polish
that test theories (ideas). astronomer Nicolaus Copernicus
in 1507. His idea was that Earth

THE SCIENCES Biology SCIENCE
Since science began over 2,000 years ago, our knowledge
of the world has increased enormously. Science has led Biology is the
to many discoveries that have transformed society, scientific study
such as cures for diseases. It’s also led to amazing new of living things. Its
inventions, such as telephones, televisions, space rockets, many branches are devoted
and computers. These practical spin-offs of science are to different kinds of life,
called technologies. including botany (the study
of plants) and zoology (the study of
Medicine Chemistry animals). The most important idea in
biology is the theory of evolution by
Medicine is the All substances are made natural selection, which explains how
science of healing of chemicals, from your living things came to exist in their
illnesses. In the past, hair and teeth to the air current form.
people believed that around you and the
diseases were a punishment for paper in this book. FOSSIL
bad behavior. Scientists now Chemists investigate Preserved remains
know that most diseases are how atoms join
caused by microscopic together in different of living things
organisms, ways to form helped scientists
inherited genes, molecules, or how
or faults with molecules break to understand
a person’s apart and recombine evolution.
immune system. to form new
substances. Astronomy

Physics Geology Planet Earth is a tiny speck of matter
in a vast universe of planets, stars,
Physicists investigate energy and Geology is the galaxies, and colossal areas of empty
movement. They study the tiniest study of the Earth space. Astronomy is the study of this
particles of matter that make up and its interior. gigantic realm beyond our own
atoms, and things that aren’t Geologists study planet. Thanks to rocket technology,
made of matter at all, such as how rocks form astronomers can now study space
time, light, gravity, and from chemicals first hand.
space. The work of physicists called minerals
led to the discovery of and how they break down or change
radio waves, which gave into new types of rock. Geologists also
us television and cell look at processes that happen deep
phone technology. underground in Earth’s interior.
These processes cause earthquakes

and volcanoes, and continually
reshape our planet’s surface
over long periods of time.

1869 18901956 19051915 1953 1989

Dmitri Mendeleyev Scientists developed Albert Einstein’s Francis Crick and James Internet Tim Berners-
was a Russian chemist. the atomic theory. theories of relativity Watson unraveled the Lee invented the World
He laid the foundations They knew how changed physics structure of DNA, the Wide Web, a new way
of modern chemistry atoms are put with new ideas genetic code inside of sharing information.
when he wrote the together and how about space, time, living things.
Periodic Table. they break apart. light, and gravity. 221

SCIENCE Mighty atoms FAST FACTS

Everything is made up of atoms. These incredibly O The period at the end of this sentence
small particles are the building blocks of all matter, covers around 250 billion atoms.
from the rocks that make up our Earth, and the O Elements are made up of atoms that
animals, plants, and other creatures that live on it, each have the same number of protons.
to the planets and stars in distant galaxies. O Protons and neutrons consist of even
smaller particles called quarks.
INSIDE ATOMS
Atoms may be small, but they ELECTRON
contain even smaller particles.
Protons and neutrons cluster
together in the nucleus at
the center of the atom.
Electrons move in a
cloud that surrounds
the nucleus. Strong
electrical forces
hold these small
particles together
inside atoms.

ATOMS Just as the images NUCLEUS
on a computer monitor consist
of tiny dots of light called PROTON
pixels, objects in the real world
are made of tiny dots of matter NEUTRON
called atoms.
LOOKING AT ATOMS
222 Atoms are too small to see. In fact, they are much
smaller than the wavelengths of visible light, so
a microscope is not much use either. Instead,
scientists “see” atoms by taking pictures of the
electric fields around these tiny particles.

Glucose Alcohol of Water

C6H12O6 C2H6O H2O

O Also known O Also known O Covers around 70 percent
as dextrose as ethanol of Earth’s surface
O First isolated O Formed by the action of O Essential for life
from raisins in 1747 by yeast on natural sugars.
Andreas Margaff Without water, life on
The word alcohol is the common Earth could not survive. This simple SCIENCE
Plants make this simple sugar using name for ethanol, which is the type molecule makes up around 70 percent
the energy in sunlight. Animals eat of alcohol found in beer, wine, and of the human body. Water is the only
these plants and other animals and spirits. In concentrated form it kills molecule that exists on Earth in three
then use the glucose in them as a germs. Doctors and nurses use it to different forms—as a solid (ice), a gas
source of energy to stay alive. clean the skin before an injection. (water vapor), and liquid (water).

Vitamin B7 Vitamin D Diamond

C10H16N2O3S C28H44O C

O Also known as O Also known O Hardest known
biotin or vitamin H as cholecalciferol substance in nature
O First isolated O First isolated O Highly prized as a
in 1941 by Vincent in 1922 by Edward gemstone for jewellery
Du Vigneaud Mellanby
Diamond is a rare form of carbon in
Vitamin B7 is one of Vitamin D is essential for which each carbon atom bonds with
eight molecules that make up the building strong bones. This molecule four other carbon atoms to form
vitamin B complex. This essential is made in the body when the skin is a tightly packed crystal structure.
vitamin is vital for cell growth. exposed to sunlight. Other sources Diamonds are very hard so they
Sources include liver, brewer’s yeast, include cereals and fatty fish. are used to make the tips of drills.
and dairy products.

MOLECULES Atoms stick together to form bigger EACH DROP OF WATER
particles called molecules. The force that holds them below is made up of three atoms—
together is called a chemical bond. Atoms form chemical one oxygen atom (light blue) and
bonds by donating or sharing electrons with other atoms. two smaller hydrogen atoms (white).

SCIENCE Solid, liquid, or gas?

Almost everything in the world exists in one of three states
of matter. Solids keep a fixed shape, liquids have no fixed
shape but fill the container in which they are held, and
gases float around in space with no fixed shape or volume.

SOLID The atoms or SOLID STATE LIQUID The atoms
molecules in a solid are The atoms or molecules in a solid substance or molecules in a liquid
packed tightly together. are held together by electrical forces. They are packed less tightly
are arranged in a repeating pattern called a than those of a solid.
crystal lattice—similar to the way apples or
oranges stack together in a grocery store.
This makes the solid dense and hard.

SOLID TO LIQUID If you heat up an ice cube to its Melting
melting point, the solid ice gradually turns into liquid
water. Ice melts at 32°F (0°C).

Freezing LIQUID TO SOLID When the molecules in liquid
water lose energy, they freeze and turn into solid ice.
Water freezes at 32°F (0°C).

Carbon crystals A diamond is made up of
many carbon atoms, which line up to form a
crystal. The arrangement is so perfect that the
carbon atoms are held very tightly. This makes
diamond the hardest substance found in nature.

224

CHANGING STATES SOLID, LIQUID, OR GAS?
If you heat a solid enough, the atoms or
molecules from which it is made get enough INTO THIN AIR
energy to break apart and slide over each
other. The solid melts and changes from O Some substances, such as iodine, can
the solid state into the liquid state. change directly from a solid to a gas
Heat the liquid further, and it boils, without first becoming a liquid. This
changing into the gaseous state. is called sublimation.
O At room temperature, dry ice

(frozen carbon dioxide) sublimes to
become carbon dioxide gas.

LIQUID STATE GASEOUS STATE SCIENCE
The atoms or molecules in a liquid The electrical forces between the atoms
substance can slide over each other, GAS The atoms or and molecules in a gaseous substance have
so a liquid can be poured into a molecules in a gas are broken down completely, so they will fill
container. But the electrical forces held so loosely that they the container in which they are held. Gases
between the atoms or molecules in a fly away into space. cannot be poured like liquids, and many,
liquid stop them from pulling apart. but not all, are invisible.

LIQUID TO GAS If you heat liquid water up
to its boiling point, 212°F (100°C), the molecules

Evaporationevaporate (turn into a gas) and escape into the air.

Condensation GAS TO LIQUID When water vapor in
the air loses energy, the molecules stick
together and become liquid water.

Liquid metal At room temperature, Heating up Solid aluminum reacts with
nearly all metals are solids. But there liquid bromine to give solid aluminum
is one exception—mercury. Mercury has bromide. The reaction produces a lot of
a melting point of –36.4°F (–38°C), so it heat, and the excess bromine boils. This
stays liquid—even if you put it in a freezer. produces brown fumes of bromine gas.

225

SCIENCE Mixing chemicals

A few common substances are made of just one chemical, such as
pure water or pure salt. Most of the things that we come across

every day, however, are combinations of several chemicals.

DISHWASHING COMPOUNDS OIL AND WATER
LIQUID is a mixture Many substances undergo changes never combine because
of soap, water, and when they are mixed together. their molecules repel
other chemicals. The chemical bonds that bind the each other.
molecules to each other break apart
and then recombine to form new
substances called compounds.

MIXTURES
Some substances do not
react when they are added

together because they
cannot form chemical
bonds. These are called
mixtures. Mixtures can
easily be separated again

because the original
substances do not change.

TAKE A LOOK COARSE SUSPENSION COLLOID These SOLUTION When
MIXTURE In some When small soil are like suspensions, one substance dissolves
O Mixtures are made of different mixtures the particles particles are mixed but the particles do in another it is called a
elements or molecules. During are large enough to with water they form a not sink to the bottom. solution. Seawater is a
mixing, some of the substances be seen and separated suspension. Eventually In milk, tiny droplets solution of salt and
may become harder to see. In easily. Gravel is a the heavier solids will of fat float in a water; air is a solution
coarse mixtures you can usually coarse mixture. sink to the bottom. watery solution. of gases.
spot each substance. Suspensions
may look like a single liquid, but
eventually they separate out.
Solutions are the most thoroughly
mixed—it is often difficult to tell
there is more than one substance.

226

MIXING CHEMICALS

SEPARATING MIXTURES AND COMPOUNDS CHEMICAL SCIENCE
REACTIONS
It is much easier to separate a mixture than a When the atoms of two or
compound. Mixtures can be separated using more substances rearrange
physical methods, such as evaporation, filtration, themselves to form a new
flotation, or distillation. Separating compounds compound, we say that a
may require several steps before you get the substance chemical reaction has taken
you want, including mixing with other chemicals, place. Most chemical
heating, and filtering. reactions are irreversible—
you cannot turn a cake

It’s elementary

SCIENCE An element is a pure substance that cannot
be broken down into simpler chemicals. An
element is made of only one type of atom.
So, the element hydrogen is made only of
hydrogen atoms, and gold of gold atoms.

WHERE DO ELEMENTS COME FROM?
Most scientists believe that much of the hydrogen and
some of the helium in the universe were formed in the

“Big Bang” that formed the universe. Hydrogen
has the smallest and simplest atoms, and
helium has the next smallest.

THE PERIODIC TABLE

Scientists recognize 117 H Every element has a one- or two-letter He
different elements, which
have been organized into HYDROGEN symbol. For example, Kr is the Kr Symbol HELIUM
a chart known as the 1 symbol for the element Krypton. 2
Periodic Table. This table
was first devised in 1869 Li Be Scientists use these symbols to write Name B C N O F Ne
by Russian chemist Dmitry
Mendeleyev, who organized LITHIUM BERYLLIUM down the chemical formulas for 36 BORON CARBON NITROGEN OXYGEN FLUORINE NEON
elements with similar 3 4 molecules and chemical reactions.
properties into groups. Atomic 5 6 7 8 9 10
The elements are arranged number Al Si P S Cl Ar
by the size of their atoms. Na Mg
Aluminum SILICON PHOSPHORUS SulfUR CHLORINE ARGON
SODIUM MAGNESIUM 13 14 16 17 18
11 12 15

K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr

POTASSIUM CALCIUM SCANDIUM TITANIUM VANADIUM CHROMIUM MANGANESE IRON COBALT NICKEL COPPER ZINC GALLIUM GERMANIUM ARSENIC SELENIUM BROMINE KRYPTON
19 20 21 22 23 24 25 26 27 28 29
30 31 32 33 34 35 36

Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe

RUBIDIUM STRONTIUM YTTRIUM ZIRCONIUM NIOBIUM MOLYBDENUM TECHNETIUM RUTHENIUM RHODIUM PALLADIUM SILVER CADMIUM INDIUM TIN ANTIMONY TELLURIUM IODINE XENON
38 39 40 41 42 43 44 45 46 47 48 49 54
37 50 51 52 53

Cs Ba LANTHANIDES Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn
or RARE-EARTH
Cesium BARIUM HAFNIUM TANTALUM TUNGSTEN RHENIUM OSMIUM IRIDIUM PLATINUM GOLD MERCURY THALLIUM LEAD BISMUTH POLONIUM ASTATINE RADON
55 56 57—71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86

Fr Ra ACTINIDES or Rf Db Sg Bh Hs Mt Ds Rg Metals are on
RARE-EARTH the left-hand
FRANCIUM RADIUM RADIOACTIVE 104 DUBNIUM SEABORGIUM BOHRIUM HASSIUM MEITNERIUM ROENTGENIUM side and center
87 88 105 106 107 108 109 110 111 of the Periodic
METALS Table. On the
La right-hand side
89—103 are gases and
LANTHANUM nonmetal solids.
57 Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

Ac CERIUM PRASEODYMIUM NEODYMIUM PROMETHIUM SAMARIUM EUROPIUM 64 TERBIUM DYSPROSIUM HOLMIUM ERBIUM THULIUM YTTERBIUM LUTETIUM
58 59 60 61 62 63 65 66 67 68 69 70 71
ACTINIUM Cm
89 Th Pa U Np Pu Am Bk Cf Es Fm Md No Lr
CURIUM
THORIUM PROTACTINIUM URANIUM NEPTUNIUM PLUTONIUM AMERICIUM 96 BERKELIUM EINSTEINIUM FERMIUM MENDELEVIUM NOBELIUM LAWRENCIUM
90 92 93 94 95 97 98 99 100 101 102 103
91

Compounds Water is a RADIOACTIVE DECAY
Most chemicals are compound made Some elements are made of atoms so
not pure elements, but of two hydrogen large they break apart spontaneously.
compounds. A compound atoms and one This is called radioactive decay, and
is a chemical made up of oxygen atom. the subatomic particles (smaller than
two or more different atoms) and energy released by it can
elements chemically
be dangerous. Each radioactive
combined. element has a half life, the time it takes

228 for half of its atoms to break apart.

Au Gold Fe Iron IT’S ELEMENTARY SCIENCE

AurumGOLD FerrumIRON He Helium

79 26 HeliumHELIUM
2
■ Group Transition metals ■ Group Transition metals
■ Discovery date ■ Discovery date Unknown ■ Group Noble gases
Unknown (prehistoric (prehistoric times) ■ Discovery date 1868
times) ■ Melting point 2,800ºF ■ Melting point -458ºF (-272ºC)
■ Melting point 1,947ºF (1,538ºC) ■ Boiling point -452ºF (-269ºC)
(1,064ºC) ■ Boiling point 5,182ºF
■ Boiling point 5,173ºF (2,856ºC) (2,862ºC) Helium is the second most
abundant element in the
Gold gets people excited. It has been Iron is a versatile and abundant metal. universe, after hydrogen. It was
prized and valued since prehistoric We use it to build bridges and make discovered in space, before we
times and turned into many crowns, machines and flatware. Iron is vital to found it on Earth. It weighs very
idols, and crosses over the centuries. your well-being. It gives red blood little and is used to make things
Gold never loses its shine and is easy cells their color and helps to carry float, such as airships and balloons.
to melt and mold. It is measured in oxygen around your body. The center It is also used in liquid form as a
carats—pure gold is 24 carats. of the Earth is made of iron. coolant in big scientific computers.

Hg Mercury C Carbon U Uranium

MERCURY Hydragyrum CarboCARBON UraniumURANIUM
80 6 92

■ Group ■ Group Nonmetals ■ Group Actinides
Transition ■ Discovery date Unknown ■ Discovery date 1789
metals (prehistoric times) ■ Melting point 2,070ºF
■ Discovery date ■ Melting point (1,132ºC)
Pre-1500 BCE diamonds 6,917ºF (3,852ºC) sublimes 8,672ºF ■ Boiling point 7,468ºF (4,131ºC)
■ Melting point -38ºF (-39ºC) (4,800ºC)
■ Boiling point 674ºF (356ºC) Uranium is a naturally occuring
Carbon is vital to all living things, and radioactive metal and was named after
Mercury is poisonous, although in on Earth it is frequently exchanged the planet Uranus. It is refined and
ancient times it was thought to have between the air, living things, and the used in industry, nuclear power
healing and life-giving properties. soil, in a never-ending cycle. Carbon plants, and warfare. In the 1940s it
Early chemists (alchemists) once atoms can join together to make coal was used to make the atomic bomb
thought it held the secret to making and diamonds, as well as with “Little Boy,” which was dropped on
gold. At room temperature, mercury other elements to make more Hiroshima in 1945.
is a liquid. than 10 million compounds.

Ca Calcium P Phosphorus WHO’S WHO?

CalcisCALCIUM LuciferPHOSPHORUS ■ Robert Boyle (1627–1691) was a
20 15 British scientist who laid the foundation
for modern chemistry and proposed the idea
■ Group Alkaline earth ■ Group Nonmetals of elements.
metals ■ Discovery date 1669, by ■ Henry Cavendish (1731–1810) was
■ Discovery date German chemist Hennig Brand the first scientist to prove water was
Pre-100 CE ■ Melting point 111ºF (44ºC) not an element, but a compound.
■ Melting point ■ Boiling point 531ºF (277ºC) ■ Joseph Priestly (1733–1804) was
1,548ºF (842ºC) a clergyman and scientist. He discovered
■ Boiling point 2,703ºF This fiery element is very several gases, including oxygen.
(1,484ºC) reactive and so isn’t found ■ Alfred Bernhard Nobel (1833–1896)
naturally on Earth. was an explosives scientist. He created
Calcium is the most abundant Phosphorus is used to dynamite and founded the five Nobel prizes.
metal found in living organisms and make matches, fertilizers, ■ Marie Curie (1867–1934) was famed
is vital for many cellular reactions. and some weapons. It is for her work on radioactivity, and discovered
It is also a key component of bones also a component of DNA polonium and radium.
and shells, giving them strength. and helps to make energy
Calcium is also found in milk, in your body. 229
chalk, and seaweeds.

Energy Freewheeling
turns potential
Energy is the power behind our world. Although you
can’t see it, you can’t do much without it. Whenever energy into
things move, light up, change shape, get hotter or kinetic energy.
colder, or make noises, energy is involved.
SCIENCE
STORED ENERGY
You can do two things with energy: store it or use it. TYPES OF ENERGY
It takes lots of energy to ride a bike up a hill, but Energy exists in many different forms.
that energy doesn’t disappear. It’s stored by your body
and by your bike in a form called potential energy. Almost everything we do involves
You use this stored energy when you race back changing energy from one form into
down without pedaling. The potential another. When we’re “using” energy, we’re
energy you stored is then converted actually converting it into another form.
into kinetic energy
(movement energy).

Kinetic Light Electromagnetic Heat Electrical Nuclear Gravitational

The energy moving A kind of kinetic Electromagnetic Hot things have Electricity is a Atoms can release Falling things, like
things have. Race energy carried by this waterfall, release
cars have lots of invisible waves of energy is also energy because their convenient form of energy from their potential energy
kinetic energy. electricity and stored using gravity.
magnetism. carried by radio atoms or molecules energy that can be nucleus (central

waves, X-rays, and move more quickly. carried along wires. core).

microwaves.

CHANGING ENERGY RENEWABLE
ENERGY
Heat sensitive photograph There’s a fixed amount of
energy in our universe. We can’t make any more or use Earth has limited amounts of
any up. All we can do is change energy to other forms. fossil fuels, such as oil, coal, and
When a car brakes, its kinetic energy doesn’t vanish. It gas. Once we’ve used them, there will
changes to heat in the brakes and wheels (glowing in this be no more. There are unlimited
heat-sensitive photograph). amounts of renewable energy. This
includes energy from the Sun, the
wind, and the oceans. We can

go on using renewable
energy forever.

230

ENERGY SOURCES Hydroelectric power ENERGY SCIENCE
Most of the energy people now
use (80-90 percent) comes Energy from moving rivers and seas Fossil fuels
from fossil fuels. The rest ■ Percentage of current energy use 6 percent
comes from renewable energy ■ Reserves left Unlimited Energy from coal, oil, and gas
and nuclear power.
Rivers flow from mountains and hills ■ Percentage of current
d TURBINES (water wheels) down to the sea. This means they energy use Oil 38 percent, coal
behind these channels generate release stored potential energy. 25 percent, gas 23 percent
electricity when water flows past them. Hydroelectric power plants capture ■ Reserves left Oil 40 years,
this energy to make electricity. gas 100 years, coal 250 years
Geothermal power
Biofuels Although bad for the
Energy from Earth’s internal heat environment, fossil fuels
Energy made using living plants and animals are still the world’s main
■ Percentage of current energy use Less than ■ Percentage of current energy use 4 percent energy source. Coal is
1 percent ■ Reserves left Unlimited ■ Reserves left Unlimited cheap for making
electricity, gas is
Deep inside, Earth is hot molten rock. Growing plants and animals store easy to pipe to
Some of this heat is released when energy we can use in the future. We homes, and oil is
volcanoes erupt. Geothermal energy can grow crops to make oil or make convenient for
means using Earth’s inner heat to electricity by burning animal waste powering vehicles.
generate hot water and electricity. such as chicken manure. Energy made
this way is called biofuel. Solar energy

Energy made from the Sun’s light or heat

■ Percentage of current energy use Less than
1 percent ■ Reserves left Unlimited

Almost all the energy on Earth originally
comes from the Sun. We can tap the Sun’s
energy directly to make electricity. Solar
panels like these turn sunlight into
electricity.

Wave power Nuclear power Wind power

Energy from the oceans and tides Energy made from Energy from air currents moving across Earth
atomic reactions
■ Percentage of current energy use Less than ■ Percentage of current energy use Less than
1 percent ■ Reserves left Unlimited ■ Percentage of current 1 percent ■ Reserves left Unlimited

Wind moving over the oceans stores energy use 6 percent Wind turbines work like propellers
energy in waves. Waves have kinetic in reverse. As their rotors spin in the
energy (because they move) and ■ Reserves left Raw uranium, wind, they turn small generators
potential energy (because they’re inside and make electricity.
above the normal sea surface). We can 80 years
use the energy in breaking waves and
shifting tides to generate electricity. Atoms are made of tiny
particles held together
by energy. Large atoms
can release this energy by splitting
apart. Small atoms can release
energy by joining together.
Most nuclear power
plants make electricity
by splitting apart
large uranium
atoms.

SCIENCE Feel the force

Forces are at work all the time, pulling you down HIDDEN
to the ground, stopping you from slipping over, and FORCES Usually
pushing you one way and then the next. Forces act you must touch an
on everything, from the tiny nuclei inside atoms to
the planets and stars that make up the universe. object to push or
pull on it. But some
PULLING AND PUSHING forces act on things
without touching them.
A force is a push or a pull. For example, your hand For example, this magnet
applies a pulling or pushing force to open and close pulls on these paper clips
a door. Forces act on all objects all of the time. They with a magnetic force.
make them move or change their speed or direction.

Your hand applies a pushing force
on a toy car to make it move.

A boxer’s fist lands a
powerful blow on a
punching bag.

Action and reaction
When the boxer punches the
punching bag, his or her fist
applies a force to move it.
But the punching bag applies
an equal but opposite force
on the boxer’s fist to slow
it down.

232

FEEL THE FORCE

FRICTION FORCES Roll a ball along LOTS OF LEVERS
the ground and eventually it will come to
a stop. Friction acts on the ball to slow it YOUR FINGERS Fulcrum
down. Try to push a heavy box along the grip the chopsticks at
floor. Friction provides grip, making it the pivot point. This
hard to get the box moving. reduces your gripping
force but magnifies
Disk brakes your finger movements.
create friction
on the brake disk MAGNIFYING FORCES SCIENCE
to slow the car. People use machines to magnify forces.
Machines called levers move around a
fixed point called a fulcrum. Most levers
magnify forces, but they act over a shorter
distance than the force you put in. Simple
levers include chopsticks, a pair of pliers,
and a nutcracker.

Fulcrum

INERTIA When there are no forces acting PLIERS convert the Fulcrum
on an object, it will either stay still or keep weak force of your hand
moving in a straight line at the same speed. on one side of the lever
This is called “inertia.” In practice, friction into a stronger gripping
usually slows down a moving object. force on the other side
of the lever.

Gravity

Gravity is the force of attraction that pulls

things together. On Earth, we experience it as

the force that pulls us down onto the surface

SCIENCE of the planet. In the universe, gravity is the

force that pulls planets in orbit around stars.

WEAK OR STRONG?

Weight and mass Gravity may seem impressive, but it is
Weighing scales measure actually the weakest known force in the
universe. It takes objects the size of planets
the pulling force that and stars to produce a noticeable effect.
Earth’s gravity exerts on The Sun’s gravity is strong enough to hold
your body. Gravity exerts
more pulling force on a all the planets of the
body with greater mass, so solar system in
the scales would register a orbit around it.
higher weight for a person

with greater mass.

GRAVITY AT WORK
Take up skydiving and you will soon feel the full
effects of gravity at work. When you jump out of a
plane, gravity makes your body accelerate toward the
ground. At the same time, air rubs against your body,
creating friction, or drag, which works against gravity.
Eventually the two forces balance, and you stop
accelerating—you have reached “terminal velocity.”

G R AV I T Y

NEWTON EINSTEIN

SCIENCE GENIUS

Electricity

SCIENCE Neutron Everything in the universe is made up of atoms that
we can’t see. Each atom has particles that transport an
Proton electric charge. Electricity powers items we use every
Electron day, from lights to computers. It is carried to our
homes by a series of cables and power plants.
Charge carriers Atoms contain
particles that carry electrical charge. CHARGED CLOUDS
Protons are found in the nucleus Lightning strikes when static
and carry a positive charge. electricity builds up in a
Neutrons are also found in the storm cloud. Negative charge
nucleus, but are uncharged. collects at the bottom of the
Electrons orbit around the nucleus. cloud, while positive charge
builds up near the top.
Eventually, the negative
charge shoots down to the
ground in a bolt of lightning.

Static electricity The buildup of TELL ME MORE...
static electricity can make your hair
stand on end. If you touch the metal Static electricity can be very handy
dome of a Van de Graaf generator, if you are a farmer. Crop spraying
positive charge transfers to your body, delivers pesticide as a spray of fine
including your hair. The hairs repel droplets. The spray
each other, making them stand on end. is given an electric
charge so that the
droplets repel each
other and spread
out over the crops.

BATTERIES Current electricity NERVES
provide power Electrons can flow through
metals and other conductors. The nerves inside your body
PAPER CLIP This flow of electrical charge work like electric wires.
acts as a switch is called current electricity, They carry messages to and
BULBS and it can be used to light from the brain to different
light up up our homes and power parts of your body in the
electrical devices such as form of electric signals.
236 microwaves and televisions.

ELECTRICITY AND MAGNETISM

Magnetism SCIENCE

Whenever there is electricity, there is magnetism.
This mysterious, invisible force draws some metal
objects together or pushes them apart.

WHAT CAUSES MAGNETISM? Compass aligns with Natural magnet Earth is a giant
The same moving electrons that create the magnetic field of natural magnet whose magnetic
electricity also create magnetism. This the bar magnet. field makes compass needles point
force acts through an invisible magnetic toward the magnetic North Pole.
field. You can see this field of force if Earth’s magnetic field extends
you scatter some iron filings around thousands of miles into space,
a bar magnet.
forming a vast area
known as the
magnetosphere.

Like poles push apart

SN N S

LIKE POLES REPEL
Magnets have north and south
poles. If you push the same poles
together they repel each other.

SN SN

UNLIKE POLES ATTRACT
Push opposite poles together and
a powerful force of attraction
will snap the magnets together.

MAGNETIC NORTH POLE MAGNETIC SOUTH POLE

Electromagnetism Magnetism

and electricity are united by the

force of electromagnetism. If A motor turns

you move a magnet next to a the blades of a

wire, electricity flows through food processor

the wire. Similarly, whenever

electrons flow through a wire,

they create a magnetic field

around the wire. Moving motor Electrons flowing through

Science of sound

SCIENCE Sound is a form of energy. It passes Good vibrations Objects can give
through air, water, and solid objects
as invisible waves. We can hear sound out sound energy when they vibrate.
because the waves make the delicate
skin of our eardrums vibrate. The This vibrating guitar string causes TUNING
vibrations are converted to nerve
signals in our brains. molecules of air to bump into each FORKS vibrate

7/7 other. The collisions between at a particular

Sound waves travel through air PEAKS AND molecules spread like ripples in a frequency, so it
at about 1,190 km/h (740 mph). TROUGHS pool, carrying the sound outwards always gives out
This is slower than light waves, which The height, or in all directions.
is why we hear the sound of a distant “amplitude”, of sound at the
jet aircraft or explosion after we see it. peaks and troughs same pitch.
Sound travels faster under water, in a sound wave
about 5,000 km/h (3,125 mph), dictates loudness. Peak

though the exact speed varies Trough
with temperature.

SOUND WAVES

Seeing with sound Sound waves bounce Echolocation SCIENCE OF SOUND
off objects in the same way light waves do.
Dolphins and bats are able to use these Seeing with sound Bat calls The echolocation
echoes to picture objects around them. calls produced by bats are
With the aid of computer-imaging loud but so high pitched
software that converts sound waves into that most people cannot
pictures, we can do the same. hear them at all. Bats have
incredibly sharp hearing
and use faint echoes from
nearby surfaces to pinpoint
prey or detect obstacles.

Light fantastic

Energy takes many forms. Light is one we are familiar with
because our eyes are specially adapted to detect it. However
seeing light is one thing – understanding it is more tricky.

HOW DOES LIGHT TRAVEL?
Puzzlingly, light behaves as though it is
made of both waves and particles. Like
waves, light can be reflected and refracted,
and its wavelength can be measured. Other
types of wave need something (a “medium”),
to ripple through, but light can travel

across a vacuum.

Shadows
Light travels in a straight line, and
cannot bend round obstacles. The space
behind an obstacle looks dark because
the only light reaching it is that reflected
from other objects nearby.
SCIENCE LIGHT PARTICLES

LIGHT WAVES

Filament

Where does light come from?
Atoms that are excited by a collision return to
their normal state by emitting light energy. The
atoms in a heated lightbulb filament shed their
excess energy by flinging out tiny packets of light
called photons, causing the filament to glow.

THE SPEED OF LIGHT ALL A BLUR
Fast-moving objects
O Light is the fastest moving thing in the Universe. It travels across empty space at the appear blurred because
unimaginable speed of 300,000 km/second (186,411 miles/second). light travels much
O One light year is the distance light can travel in one year. This is about 9.5 trillion km faster than our brain
(5.9 trillion miles). Light years are used to measure colossal distances across space. takes to interpret what
The Sun is a mere 499 light seconds away. we are seeing.
O Albert Einstein worked out that if there was a way to travel at close to light speed,
time would slow down and you would age more slowly.

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REFLECTION When light strikes an The break in the LIGHT FANTASTIC
object, some of it is bounced back or straws is an
“reflected”. The angle of reflection is illusion caused REFRACTION When light
always the same as the angle at which by refraction. crosses the boundary between
the light hits the surface, so on a smooth two media with different
surface we see a perfect reflection, or densities (such as air and water), SCIENCE
mirror image. If the surface is curved or it bends, or “refracts”. This is why
uneven, the image is distorted. objects standing in water appear
distorted at the surface. If you try to
touch a coin or pebble in a bucket of
water, it will not be exactly where
your eyes tell you it is.

Lenses A lens is a transparent
object with curved surfaces that
refract light in a predictable way.
An object close behind a bulging
or “convex” lens will appear
magnified while one seen
through a dished or “concave”
lens will appear reduced in size.
Telescopes, microscopes, and
spectacles all use lenses.

IMPERFECT eyesight can be
corrected with artificial lenses.

Concave lens

Spectrum WOW! RAINBOWS
We see rainbows when white
The universe is full of electro- To remember the colors of
magnetic radiation, which travels the visible spectrum in order, light is refracted as it passes
in waves. Our eyes see a small memorize this phrase: “Roy G. through different media,
range of these waves as visible
light, but we can also detect Biv”, for Red, Orange, Yellow, such as drops of water or
the effects of other
radiation types. Green, Blue, Indigo, thin layers of oil. Sunlight

and Violet. passing through rain or mist

SCIENCE from a fountain creates

rainbows, and we see them

produced by solid materials

such as crystal or perspex.

Prism When waves strike the surface of a
different medium at an angle,
White light contains they are bent by an amount that
a mixture of visible differs slightly for different
wavelengths. wavelengths. The bending is
known as “refraction”.

THE ELECTROMAGNETIC SPECTRUM Because short
The visible spectrum is a small part of a much larger wavelengths refract
spectrum of energy waves. We have found technological more than long
uses for most types of electromagnetic radiation. ones, the different
wavelengths of the
spectrum are
separated by
the prism.

The wavelengths of different types
of electromagnetic radiation range
from shorter than an atom to
millions of miles long.

WAVELENGTH

GAMMA RAYS X-RAYS ULTRAVIOLET (UV) VISIBLE RAYS

Gamma radiation X-rays pass Ultraviolet Visible light
is immensely through our rays damage waves make the
powerful. In large bodies. We our cells. world a colorful
quantities it can use them Sunscreen or a place for us
damages our cells to take pictures suntan can help to experience
and DNA. of our insides. filter them out. and enjoy.

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SPECTRUM

COLOR VISION

Color vision Objects appear A tomato absorbs Lemons reflect red and Blackberries absorb Green peppers reflect SCIENCE
colored to our eyes because their green and blue light
surfaces reflect some wavelengths of and reflects red. green light, which we all colors of light, green light and
light but not others. Plants have
chemicals called pigments that color see as yellow. reflecting very little. absorb red and blue.
their fruits and flowers, making
them attractive to the animals that
disperse their pollen and seeds. Most
fruit-eating animals see in color.

Adding color Magenta Subtracting color
Televisions produce Paints create colors by absorbing
hundreds of colors by Yellow light rather then emitting it.
mixing red, green, and
blue light in different Mixing the primary paint
quantities. Blending colors of magenta, yellow,
these three primary and cyan creates new colors
wavelengths to create by reducing the range of
wavelengths that are
new colors is known
as color addition. Cyan reflected. This is called
color subraction.

You see green light COLOR PRINTING
because the ink used here The microscopic dots used in
absorbs all other color color printing come in four
wavelengths. colors, but blend to create the
illusion of thousands more
Unstoppable waves ( p.168–169).
Electromagnetic radiation is everywhere.
Visible light is bouncing off this page,
allowing you to see the words and pictures
printed in different colors. But other kinds
of electromagnetic wave are passing straight
through the pages and through your body
without you even noticing.

INFRARED (IR) MICROWAVE RADIO WAVES radio, and TV
sets convert the
Warm objects Microwaves Data, sound, waves back into
emit IR radiation. make certain and pictures can images and sound
IR cameras see molecules move be transmitted for us to see
heat as white or very fast and as radio waves. and hear.
red. Cool objects give out lots of Devices such
appear blue. heat energy. as telephones, 243

SCIENCE Evolution The father of evolution
The English naturalist
Over long periods of time, all species of Charles Darwin first
organism slowly change. This gradual
change, called evolution, is driven by the proposed the theory of
process of natural selection. This process evolution after studying
allows organisms that are best suited to their hundreds of different
environment to survive and reproduce. animals, plants, and fossils.
He realized that many
NATURAL SELECTION species were related and had
Darwin observed that most animals and plants produce a common ancestor. Modern
more offspring than survive to become adults. He realized DNA testing is now proving
that nature was selecting those with the characteristics that his theory was correct.
best adapted to their surroundings, allowing them to
pass on their characteristics to future generations. ARTIFICIAL SELECTION
In the wild, species evolve by natural
selection. However, humans have been
helping evolution by choosing animals and
plants with desirable characteristics and
breeding them to produce sheep with more
wool, cows that give more milk,
and crops that have better
yields. This process is
called artificial selection.

Domestic dogs All dogs are Broccoli
descended from wolves. Over (flowers)
time, humans selectively bred
them for things like hunting
or herding ability, speed, and
size, so that we now have
hundreds of different species.

SURVIVAL TACTICS ADVANTAGE Having Gray wolf Cauliflower
Frogs produce hundreds of a long neck allows the (flowers)
eggs but only a few grow giraffe to eat leaves that These dogs all
into adult frogs. other species cannot reach. have a little bit Wild cabbage
of wolf in them.
Adaptation Darwin’s theory can explain
why a giraffe has a long neck. In
the search for food, those that
could reach a little higher had
an advantage over those with
shorter necks. Over time, new
generations developed longer
and longer necks.

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THE FOSSIL RECORD EVOLUTION SCIENCE
Fossils show that life on Earth has changed Family trees Scientists trace
throughout its history. Each major layer evolution by examining fossils and
of rock contains species that are slightly seeing where they fit on the family
different to those below or on top of it. tree. Many elephant fossils have been
Although it is not easy to find fossils that found that show how these animals
show every change in a species, this birdlike developed tusks and a long trunk,
Archaeopteryx (right), is a clear example that but not all are direct ancestors of
birds evolved from feathered dinosaurs. modern elephants.

Phiomia Asian
elephant
Brussels sprouts
(large buds)

Red cabbage Moeritherium Gomphotherium Deinotherium
(leaves)
EVOLUTION AND GENES

7/7 Genes and DNA

SCIENCE There are about 30,000 genes Unless you are an identical twin, your body is built
in the human genetic code. Some according to a unique set of biological instructions,
appear just once and others repeat your own genetic code. These instructions, or genes,
many times. About 99 percent of are present in all cells and are passed from parent
to offspring.
human genes are identical to
chimpanzee genes. Even more DNA FOR DUMMIES

amazingly, you share about Genes are made of a substance called Deoxyribose
75 percent of your genes
with a dog! Nucleic Acid, or DNA. DNA is a very long molecule,

DNA has two chains, linked found packed up tightly in the chromosomes in the
by molecules called bases, which
always pair up the same way. nucleus of every cell. Cell membrane
Guanine pairs with cytosine;
thymine with adenosine. The Nucleus
order spells out the genetic code.

DNA

Chromosomes CHROMOSOMES Human CELL All living things
beings normally have 46 chromosomes are made of cells. When cells
in every cell, except gametes (egg and divide, the nucleus divides,
sperm cells), which have just 23. too, and the genetic message
is duplicated in each
new cell.

IN THE GENES +=
If a person inherits two different
genes from their parents, often one
will dominate the other. For
example, the gene for brown eyes
overrides the one for blue eyes.

TIMELINE OF MEDICINE

1859 1860 1869 1953

Charles Darwin’s Gregor Mendel’s Friedrich Miescher James Watson and Francis
book Origin of experiments on pea extracts DNA from Crick discover the structure of
Species outlines plants prove the cells. He calls it
the importance of existence of genes. “nuclein.” DNA and show
inherited traits in how it can
evolution. copy itself.

TAKE A LOOK: GENOME GENES AND DNA

■ A genome is the entire genetic code FACT FILE SCIENCE
inside an organism. The first genetic
code to be sequenced in full was that of ■ Scientists can “cut and paste” genes
a virus known as bacteriophage phi from one species into another to create
X174, in 1975. In 1984, the first useful characteristics. The genetically
bacterial genome was sequenced, and in altered organism is described as
1990 scientists began to sequence the “transgenic.” Transgenic bacteria are
human genome. The project took 13 used to produce useful drugs, and
years to complete. They found that the transgenic mice are used to research
genes were padded out by sequences of cures for many diseases.
“junk DNA,” which had no obvious
function. The human genome contains u THE CHROMOSOMES in this
about three billion base pairs and codes preparation have been treated to
for roughly the same amount of data make a particular gene glow green.
that can be fit on one CD.

GM crops Genes can be transferred u GLOW FOR IT These mice were
into plants to create transgenic, or given a jellyfish gene to make them glow
“genetically modified” (GM) crops. in the dark.
GM technology has been used to
produce rice enriched with Cloning means using DNA from
vitamins, corn and cabbages that an organism to create an identical
produce their own insecticides, new individual, or clone. Some
and soybeans that survive being clones occur naturally—many plants
treated with weedkillers that kill and some simple animals reproduce
all other plants. by cloning, and identical twins
are clones. Artificial cloning
u CYSTIC FIBROSIS is caused by can be used to grow new
a mutation in a gene controlling the organs for transplant
production of sweat and mucus. patients.

Genetic diseases Some genes u CHEMICAL CURE In the future, . DESIGNER
contain errors that cause them to GM crops should reduce the need to treat BABY
malfunction. These faulty genes can fields and orchards with chemicals that
cause diseases such as cystic fibrosis may harm the environment. Would you pick
and sickle cell anemia. Most disease and choose which
genes are “recessive,” like the gene for genes to pass on to
blue eyes, meaning the disease only
develops if a child inherits a faulty your children?
copy from both parents.

1961 1970 1990 1996 2003

Marshall Nirenberg Frederick Doctors use gene The first The completed sequence of
deciphers the genetic Sanger begins therapy for the first experimentally the human genome is
code hidden in the sequencing time, treating a four- cloned mammal, published.
order of the bases. DNA. year old girl suffering Dolly the sheep,
from an is born.
immune disorder.

SCIENCE Forensic science

Forensic science helps the police fight crime. Most people think of murder
investigations when they talk about forensics, but forensic scientists deal with
a range of crimes. Some are computer specialists who trace “cybercriminals”
on the Internet, for example, while others are art experts who identify forgeries.

CRIME SCENE DO NOT ENTER CRIME SCENE

CRIME SCENE
Crime scene investigators collect the evidence
at a crime scene. They look for any clues that might
secure a conviction, from bloodstains and body fluids
to fibers and footprints. Crime scene investigators

photograph all the evidence and then take it
back to the crime lab for further analysis.

Post mortem After any suspicious
death, a doctor called a pathologist
will do a post mortem. This involves
cutting open the body to find out the

cause and time of death. If the
corpse has been dead for a long
time, the time of death can be

established by studying the
kinds of insects present.

FINGERPRINT FEATURES Double loop Whorl FORENSIC SCIENCE SCIENCE
If you look at your fingertips, you will
notice they are covered in tiny ridges. DNA fingerprinting
The ridges form distinct patterns of Everyone has a unique DNA
arches, loops, and whorls. No two sequence (except for identical
people have been found to have the twins). Forensic scientists can
same prints (not even identical twins) turn a DNA sample into a
so they can be used for identification. fingerprint by breaking the
DNA into small fragments
and then making these spread
Arch through a sheet of gel to
form a series of bands.

DO NOT ENTER CRIME SCENE DO NOT ENTER

Leaving prints Dusting brush Digital data d IRIS SCANS The scanner
Criminals leave prints Long gone are the days of using records the features of the iris,
on everything they touch. ink to record fingerprints on
Prints left in blood stains show up paper. Instead, the police use which is unique to each
clearly. Other visible marks can be left electronic scanners to record the person.
on soft materials such as soap. Latent prints digitally. The police store
prints are made by the prints on a database, which
natural skin oils. can then be used to match the
These prints show prints found at crimes scenes.
up when forensic A new development is iris
scientists dust scanning, which looks at
the crime scene. the colored tissue
around the pupil.
. DUSTING FOR
PRINTS A forensic . FINGER SCAN
scientist dusts a window A scanner records
to reveal a set of prints the pattern of arches,
hidden on the glass. loops, and whorls that
make up a fingerprint.

TAKE A LOOK: FACE FROM THE PAST Cybercrime
Crime involving computers is on
Forensic scientists have studied skeletal extremely important. It has helped the the increase. The crimes often
remains. They can help forensic artists police solve crimes that happened involve people stealing credit-card
to build up a 3-D image of the face decades ago. It also reveals what people details and pretending to be
from the skull. Facial reconstruction is from ancient civilizations looked like. someone else. Computer experts
are helping the police to track
down these cybercriminals.

u DEPTH MARKERS u FACE SCULPTURE u SKIN DEEP The artist
The artist makes a cast of the The artist uses a modeling adds a layer of clay to form
skull. Pegs act as depth tool to build up the muscle the skin. The head is now
markers for skin and muscles. layers with modeling clay. fully reconstructed.

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