Children's Illustrated Encyclopedia

Judaism

JewiSH feStivalS THe HiSTory oF THe JeWiSH PeoPle and of their religion,

Judaism, are closely linked. all Jews believe in one god who, more than
4,000 years ago, made a special agreement with their ancestor, abraham.
Yom Kippur (day of They were to become god’s chosen people. in return, they promised to
atonement) Tenth day obey his laws and worship no other gods. Jews believe that a messiah, god’s
of new year; holiest of messenger, will one day come to transform the world into a better place
festivals, with 24 hours and to restore the ancient Jewish kingdom that was destroyed in the
of fasting. 6th century bce. Judaism aims for a just and peaceful life for all people on
Purim (Feast of lots)
early spring festival.

Passover (Pesach) eight- earth. Jewish scriptures explain that to achieve this aim, correct behavior is
day spring festival. very important. orthodox Jews—those who interpret the scriptures very
Shavuot (Feast of
Weeks) Harvest festival strictly—obey many rules about their day-to-day activities, including how to
in the early summer.
dress and what to eat. For example, they do not eat pork or shellfish. many
Rosh Hashanah (new Jews, however, are not orthodox and apply the rules less strictly. For all Jews,
year) early fall. Hebrew is the language of worship. it is also the national language of israel,
Sukkoth (Feast of the Jewish homeland. However, Jews live and
Tabernacles) nine-day work all over the world, speaking many Jews light candles in a
fall festival. different languages. Their strong menorah, or branched
Hanukkah (Festival of family life and the laws that
lights) eight-day candlestick, during
winter festival. Hanukkah.

guide them unite them
wherever they live.
Jewish men
wear a skull
cap called a
yarmulke or
kipa.

Talmud
Jewish religious leaders are called
rabbis. They are responsible for
teaching and explaining the
laws of Judaism. They study
two holy books: the Talmud
(right) and the Torah,
which is kept as a scroll. The
Talmud contains instructions
for following a Jewish way of
life and understanding
Jewish laws.

During prayers, Jewish The Talmud
men wear a tallith, or contains
prayer shawl, over instructions for
their shoulders. following the
Jewish way of life.

ToraH

The first five books of the Hebrew Bible—
the Torah (left)—contain the laws of
Judaism and the early history of the
Jewish people. other sections of the
Hebrew Bible contain the psalms, the
words of the prophets, and other holy
writings. For Jews, the Torah is the
most important of books.

Synagogue Find out more
Jews worship in the synagogue. Prayer, study, and special israel
family occasions, such as weddings and bar and bat mitzvahs
(the celebrations of children becoming adult Jews), take place middle east
here. a minyan (quorum of 10 males) is required to formally religions
recite Kaddish (memorial prayers) and read from the Torah.

299

K jOHN F.

ENNEDY

1917 born in brookline, An AssAssin’s bullet abruptly ended the promise that John Fitzgerald
Massachusetts.
1940 Graduates from Kennedy brought to the American presidency. His family name meant
Harvard university. politics in their hometown of boston. Kennedy graduated from Harvard
1941-45 serves in us navy university, and then served in the us navy. After the war, Kennedy launched
during World War ii. his political career, serving first in the House of Representatives, and then
1946 Wins election to us in the senate. in 1956, he began a long campaign for the presidency, which
House of Representatives. ended with his winning by a small margin in 1960. He brought youth and
1952 elected to us vigor to the White House, and his wife Jackie became a fashion icon.
senate.
1953 Marries Jacqueline tHe Kennedy dynAsty WARtiMe HeRo
bouvier. Kennedy served in the us navy
1960 elected 35th Kennedy was born into America’s during World War ii. After saving his
President of the us. most glamorous and famous political crew in an encounter with a Japanese
1961 berlin Wall divides destroyer near the solomon islands,
east and West berlin. dynasty. His grandfather was a state he was awarded a medal for bravery.
1962 Presides over the senator in Massachusetts, and his
Cuban Missile Crisis.
1963 Assassinated in father served as ambassador to Great
dallas, texas. britain. His mother’s father was mayor

In his time, President of boston and a us congressman.
Kennedy was the three of the nine Kennedy children
youngest man elected
president of the developed political careers: John;
United States, and Robert, who became attorney general
the first Roman
Catholic to hold during his brother’s presidency, and
the office. then served as a us senator for new

york until his own assassination in
1968; and edward (known as ted),
who represented Massachusetts in
the senate until his death in 2009.

Cartoon of Cuban
leader Fidel
Castro

CubAn Missile CRisis John Kennedy
When satellites revealed soviet missiles in was also
Cuba within striking distance of several us awarded the
cities, Kennedy ordered a naval blockade. Purple Heart, a
For 13 days, the world was on the brink of medal given to
war, until the missiles were withdrawn. those wounded
in action.

Kennedy’s AssAssinAtion
in 1963, Kennedy and his wife, campaigning in
texas, rode an open-top car through dallas. shots
rang out and Kennedy slumped down. He died half
an hour later. Police arrested lee Harvey oswald,
who denied the shooting. two days later, as oswald
was taken to prison, he was killed by a lone gunman

in front of a nationwide television audience.

A neW beGinninG Find out more
Cold war
Kennedy campaigned for president with the promise Presidency
of a new frontier for Americans. Although many
voters worried about his lack of experience, Kennedy World war ii

defeated Richard nixon. in his inaugural address,
Kennedy urged Americans to, “Ask not what your country can
do for you—ask what you can do for your country.” during
Kennedy’s short time in office, the us had its first manned space
flights, the civil rights movement brought equality closer for
African Americans, and the testing of atomic bombs was outlawed.

300

KMartin Luther

ing, jr.

in 1963, a baPtist Minister from alabama led 250,000 people in a
march on Washington, D.c., and delivered a moving and powerful speech.
He was Martin luther king, Jr., and his mission in life was to achieve equality
and freedom for african americans through peaceful means. under his
leadership, the civil rights movement won many victories against segregation
laws; laws that prevented blacks from voting, separated blacks from whites
in schools and other places, and gave white people better opportunities
1929 born, atlanta, georgia.

and more freedom. Martin luther king, Jr. encouraged people to practice 1954 baptist minister.
nonviolent protest: demonstrations, “sit-ins,” and peaceful disobedience 1955 earns PhD in
of the segregation laws. king went to jail several times and faced constant Philosophy.
threats of violence and death, but he continued to work for civil rights. 1955-56 leads Montgomery
bus boycott.

some white people hated him because he wanted to win more rights for 1957 southern christian
black people, and some black people disliked him because he refused to leadership conference.
use more extreme and violent methods. king was assassinated in 1968, but 1963 March on Washington,
his dream of a country without racial discrimination lives on today. in 1986, D.c.
the united states began to observe a national holiday in his name. 1964 nobel Peace Prize.
1965 selma-Montgomery
march.

Public sPeaker 1968 assassinated.
1986 Holiday established.

Martin luther king, Jr.’s words
inspired millions of americans,
black and white. at the august 1963 march on
Washington D.c., king made a speech that has since
become famous. He said, “i have a dream that one
day this nation will rise up and live out the true meaning

of its creed: We hold these truths to be self-evident;
that all men are created equal.”

civil rigHts
MoveMent
black americans
remained second-
class citizens
throughout the bus boycott
southern states until in December 1955, rosa Parks, a black seamstress who
very recently. they were worked in an alabama department store, was arrested
not allowed to vote, and for refusing to give up a bus seat reserved for white
restrictions were placed people. For one year, Martin luther king, Jr. and
on where they could sit on his friends persuaded people to boycott (refuse to
buses and in restaurants. use) every bus in Montgomery, alabama, until the
During the late 1950s, segregation of the bus seats was declared illegal.
a movement arose that
demanded equal rights for
all americans. Martin luther
king, Jr. and others organized Find out more
nonviolent protests designed
to force changes in the law. civil rights
in 1964-65, racial discrimination Human rights
was finally outlawed throughout
the united states. slavery
united states, history of

301

Knights and heraldry

a Thousand years aGo, men who fought in battle on horseback were called knights.
at first they were just powerful warriors who terrified the enemy’s foot soldiers. But by the
Argent a 13th century, the knights of western europe had an important role in society. They fought
mullet azure in the armies of the king or queen in return for land. Knights also protected the peasants
Vert a lily or who lived and worked on the land, and in exchange the peasants gave the knights their
Ermine a cross service and produce. heraldry developed as a way of identifying knights in battle. armor
crosslet gules completely covered the knights’ faces and bodies, and they all looked alike. Thus, each
knight chose “arms”—a unique colored pattern
or picture that everyone could recognize. he
displayed his arms on a linen tunic worn over
his armor. This was his “coat of arms.” The knight's
The chosen pattern remained in the symbol, or device,
was painted or
sewn on to all
knight’s family and was passed on his equipment.

from father to son.

A fall from horseback
meant defeat, and
often injured the
knight.

Azure a
dolphin argent

Sable a
bee or

Gules a lion TournamenTs and jousTinG Chivalry
rampant or The period between the 11th and 14th centuries is often
Or a chief Tournaments began in France in the known as the “age of chivalry.” Knights of the time were
indented purpure middle of the 11th century as peacetime supposed to follow a special code
training exercises for knights. They soon of chivalry—a system of rules
developed into major events with elaborate
rules. Teams of knights fought fierce mock about honor, obedience
battles over great areas of land, and the to God and the king, and
losing side paid a ransom or handed over protecting the weak. in
valuable possessions. during the 13th century,
tournaments became better organized and took place reality, many knights
in a single field. only two knights jousted at a time, or fought forgot the code. They
with blunt weapons. later, tilting replaced jousting and the honored only people
knights used lances to knock their rivals to the ground.
of noble birth and
stole from the

poor and weak.

Argent a talbot Azure a fess Gules a Azure an owl Vair a chevron In English legend,
statant sable erminois lymphad argent argent sable Saint George was a
chivalrous knight who
rescued a maiden from

a dangerous dragon.

302

Knights and heraldry Argent a
thistle proper
Knighthood
the training to become a knight started at seven years of age. girls Or a lion
were not allowed to become knights, but boys began as pages in the passant gules
household of their father’s lord. Pages learned the rules of knightly
service and how to use weapons. At the age of 15 or 16, a page became
a squire. the squire was the personal servant to his master and learned
the skills needed for fighting on horseback. After five years, the squire
could become a knight. At first, this was an honor that any knight

could bestow on a squire. today, only English kings and
queens can grant knighthoods, but the title is a formal
one given to people who deserve national recognition

and has lost most of its original meaning.
Dubbing a squire, or tapping him
on the shoulders with a sword,
made him into a knight.

Once he became a knight, Gyronny argent
the squire had to supply and gules
his own equipment.

the knights of the round table Argent an eagle
King Arthur and his knights are said to have held their court displayed sable
at a round table in the ancient capital of Camelot. if it really
did exist, Camelot was probably built in the west of britain
some 15 centuries ago. According to legend, Arthur led his
band of Celtic knights in battle against saxon invaders. the
knights of Camelot became heroes and had many adventures.

Caerleon Castle, Wales, possible site of Camelot

Knights hosPitAllErs Sable a cross
Knights from northwest Europe fought in engrailed or
Gules a rod of
the Crusades—a series of religious wars Aesculapius or
between Christians and muslims that took
place in the middle East during the 11th,

12th, and 13th centuries. the warriors
formed powerful alliances, one of which was

the Knights hospitallers. this group set up
hospitals along the Crusaders’ routes to war.

shiElds nAming shiElds
the blazon, or description, below each shield
Each knight displayed his arms on a shield. the shield had two names the field and charge and gives their
parts: the field, or surface, painted in a plain color or a pattern; colors and other details in a language based
and the charge, which displayed a symbol, such as an animal or on medieval French.
bird. the arms appeared everywhere on the knight’s equipment.
sometimes the area above the shield design might show an image The charge is a dragon KEy to blAzons Azure a harpy or
of a helmet with a crest, silk wreath, and mantling (a cloth for vert (green). He is sitting Argent Silver Vert a unicorn
protection from the sun). the knight’s motto, or slogan, could also “sejant”—with forepaws Azure Blue rampant argent
be added below the shield. the full combination of designs was on the ground. Gules Red
called a heraldic achievement (a herald was an expert in arms). Or Gold
Purpure Purple
Sable Black
Vert Green

The field on this
shield is or (gold).

Gules a barrel Argent a rose Vert a Sable a boar’s Or a dragon sejant vert Find out more
palewise or gules garb or head erased or Armor
Castles
303
Christianity
Crusades

medieval europe

korea Volcano Mountain Ancient Capital Large Small
monument city city/ city/
town town

The KoreAn penInSulA has a long history norTh
KoreA
of invasion and occupation by its two powerful
neighbors, China and Japan. In 1948, it was Area: 46,540 sq miles
The Korean peninsula is bordered divided into Communist north and democratic (120,538 sq km)
by China and, in the far northeast, South, and the invasion of the South by the north Population: 24,983,000
russia. on the west, it is bordered led to the Korean War (1950-53). The war Capital: pyongyang
by the Yellow Sea and, in the east, devastated both countries, but their subsequent Languages: Korean, Chinese
the Sea of Japan. The peninsula is histories have been very different. South Korea, Religions: non-religious,
divided, along the 38th parallel, once a rural society, became a major industrial traditional beliefs,
into north and South Korea. power, and one of the world’s leading ship- Ch’ondogyo, Buddhist
builders and car manufacturers. It also became Currency: north Korean
a center of high technology and electronics. Won

The economy of the north, an isolated and S. FED.
repressive Communist regime, is a marked
contrast. heavy industry has created severe RUS

pollution, and nationwide electricity
blackouts are common. Floods A Tumen
Najin

and droughts have wrecked N Paektu-san Hamgyong-sanmaek Ch’ongjin
harvests and many 2750m
people suffered SCALE BAR
I

great hardship. H Hyesan 0 50 km
C Kanggye
norTh KoreA k 0 50 miles

e Kimch’aek

a

The Communist republic of north Korea Ch’osan m

invaded the South in 1950, leading to the n
Korean War (1950-53). The border that
now divides the two countries is the most a NORTH
militarized in the world. north Korea
now has one of the world’s largest military s
organizations, a huge army, and an
advanced arms industry. Its military Yalu Huich’on -
might is regularly displayed at
regimented parades. Sinuiju m Sinp’o KOREA
Hamhung
gaTnagedo g-n

Chongju angni East Korea S e a o f J a p a n

Sinmi-do N Wonsan Bay

Sunch’on (East Sea)

Korea PYONGYANG

Bay Namp’o Kosong (North and South Korea have been divided
by a ceasefire agreement since 1953)
Changyon Sokcho
Sariwon Ta
Haeju Gangneung
Ongjin Chuncheon ebaek-sanmaek

Paengnyong-do SEOUL Donghae N
(SÔUL)
Incheon

Yellow Suwon Chungju W E
Sea
Cheonan Andong

SEJONG CITY Sangju

gInSeng SOUTH Daejeon Gimcheon S
Korea is a major exporter KOREA Pohang
of the valuable ginseng root, Gunsan
believed to improve health, and Daegu
promote long life and vigor. Ulsan

SouTh Namwon Masan Busan
KoreA
Area: 38,502 sq miles Gwangju Geoje-do
(99,720 sq km)
Sacheon

Mokpo GeogeuNma-dmohae-dSotrait J A P A NTsushima
Chin-do
Ko-saki

Population: 49,115,000 Jeju Strait Korea

SCapital: Seoul, Sejong eoul Jeju East China Sea
City (administrative) Seoul was the capital of Korea from 1394 to
Languages: Korean, 1948, when it became the capital of South
Chinese Jeju-do Find out more
Religions: Mahayana Asia
Buddhist, protestant, Korea. It is a fast-expanding city of over 9 million
roman Catholic, people. The orderly, rectangular street patterns of the city Asia, history of
Confucianism center give way to sprawling suburbs on the low surrounding China
Currency: Won hills. Seoul is a major commercial and manufacturing center,
with many small-scale textile factories. It is congested with Communism
traffic, and pollution is becoming a major problem. Japan

304

SOVIET Korean war
UNION
IN the mIdst of the Cold War, a “hot war” in korea
CHINA
brought world superpowers head-to-head in a bloody conflict. on
NORTH Armistice line, 1953 June 25, 1950, 90,000 North korean troops, trained and armed by
KOREA 38th parallel the soviet union, poured over the border into south korea. the
Pyongyang united Nations (uN) demanded a withdrawal, but the fighting
continued. In its first military role, the uN sent troops from 16 of its
Incheon Seoul member nations, commanded and led by the united states, to fight
alongside the south korean army. China soon entered the war on
SOUTH JAPAN the North korean side. three years of brutal fighting ended with
KOREA
Busan an armistice agreement in 1953, but
despite the huge
North aNd south korea loss of life, little
Communist-ruled North korea and us- had changed.
supported south korea were divided at the
38th parallel of latitude after World War II. United Nations troops
Both North and south korea claimed possession pose for a photo
of the entire country, and their troops often at the 38th parallel.
clashed at the border in the years leading up
to North korea’s invasion. No peace agreement
was negotiated after the war, and tensions
between the two nations continue to this day.

United
Nations
helmets

uNIted NatIoNs War oN laNd
the united Nations had only been in existence
for five years when the korean War began. the In the early stages of the war, the North korean
organization chose to play a military role for army easily advanced to the south korean port
the first time in its history, presenting a major
challenge to its member nations. of Busan, in the southeast of the country. But
uN forces surprised the North koreans with an

amphibious landing at Incheon in 1950. uN
troops advanced far into North korea, but after

China entered the war, they retreated south.

Korean GeNeral maCarthur
civilians flee President truman named General
the fighting. douglas macarthur as commander-in-

Korean War history 1951 seoul is captured by North chief of the uN forces. however,
1950 North korean troops korean forces, then reoccupied macarthur wanted to expand the war
invade south korea. by uN forces; truce talks begin. and attack targets in China, so truman
1950 uN enters the war. 1952 uN plan rejected; removed him from command in 1951.
1950 uN forces stop the truce talks broken off.
deepest North korean advance. 1953 North korea accepts the humaN Cost
1950 allied troops land uN plan; armistice agreement the korean War devastated the entire
behind enemy lines at Incheon. ends the fighting. country. more than a million south
1950 China enters the war korean civilians were killed and several
in support of North korea. 305 million more were made homeless. the
North koreans lost an estimated 1,600,000
troops, while 57,000 uN soldiers were killed.
despite these losses, korea remained a
divided country, with few political changes.

Find out more
Communism
Cold war

korea
united nations

Labor movement

Much of what workers take for granted today—fixed working

hours, a minimum wage, paid vacations, a safe workplace, and the power
to negotiate—was gained after years of bitter struggle by working people.
During the Industrial revolution, there were few laws to govern how
companies treated their workers; as a result, hours were long, pay was
low, and working conditions were poor. from the 1830s, workers joined
together to form the first unions. By the 1880s, national unions had
successfully won better working conditions, while meeting opposition
from employers. Public opinion turned in favor of workers’ rights, and
legislation in the 1930s brought about the first national labor policy.

strIke Samuel workers unIte
Gompers
the struggle for workers’ rights as more people started
turned violent in the years following to accept the need for
the civil war. Many workers, from
shoemakers to newspaper organized labor, the first
carriers, and powerful national unions
railroad workers emerged. the american
to coal miners, federation of Labor
felt they had no (afL), a group of skilled
recourse but to craft unions headed
strike, or refuse to by cigar maker samuel
work. In an effort to stop strikes, gompers, was founded
owners hired their own security in 1886. under his
forces (above) and pressured the leadership, the afL won
police to fight back. Many striking eight-hour days, shorter
workers lost their jobs, and some working weeks, safer
met with violence and even death. working conditions, and
the right of the union to
negotiate directly with the
employer. the afL grew
quickly—by 1901, there were
over one million members.

workers’ rights 1935 committee for Industrial woMen LaBor LeaDers
1834 first national labor union, the organization (cIo) unites unskilled as the Industrial revolution
national trade union, is founded. and semiskilled workers. exploded, the need for cheap
1860 shoe workers in Lynn, Ma, 1935 congress passes the national
strike and win better wages. Labor relations act. labor sent women—and
1869 noble order of the knights of 1938 congress passes the fair children—into factories,
Labor unites nearly 750,000 workers. Labor standards act. especially in the garment
1886 skilled workers form the 1955 afL and cIo merge.
afL (american federation and textile industries.
of Labor). Many women workers
joined unions to highlight
President Roosevelt’s exploitation and seek better
New Deal legislation working conditions and pay.
Elizabeth Flynn successfully led a
helped strengthen unions. waiters’ strike in New York in 1919.

LaBor LegIsLatIon afL–cIo
Prior to the 1930s, there were the congress of Industrial
few national labor laws, and organizations (cIo) was
employers used the courts to established in 1938 to organize
halt union activity. as part factory workers. In 1955, the
of his new Deal program, afL and cIo combined their
President franklin D. strength. the opportunity for
roosevelt introduced new and
sweeping laws regulating labor massive strikes gave the unions
unions. In 1932, a new law limited the greater political influence.
use of courts in labor disputes, and made
it illegal for employers to ask job seekers Find out more
to pledge not to join unions. the Labor civil rights
relations act of 1935 gave workers
the right to form unions without congress
interference from their employers. Industrial revolution

306

LAKE And RIVER WILdLIFE

THE WATER IN LAKES and rivers is teeming with all kinds of Pickerell
weed
life. Grasses, reeds, and other plants grow along the water’s FRESHWATER grows at
edge, providing food and shelter for insects, nesting birds, the water’s
and mammals, such as water voles and muskrats. In rivers, The water in lakes and rivers is edge of
the fast-flowing water sweeps away plants, but in lakes, tiny called freshwater. Although it
floating plants are food for small creatures, such as water makes up only about 0.03 percent lakes and
fleas and shrimps, which are, in turn, eaten by bigger fish. (that is, 1 part in 3000), of all the rivers.
Larger, floating waterweeds provide shade for basking fish.
Fallen leaves, animal droppings, and rotting plant matter form water on Earth, freshwater is
a rich mud at the bottom of rivers and lakes, where worms, home to thousands of different
snails, and other small organisms live. Today, many lakes and plants and animals.
rivers are suffering from serious pollution. Industrial
chemicals, farm fertilizers, untreated sewage, and a host of
other damaging substances discharged into lakes and rivers
have upset or destroyed the natural wildlife balance.

MUSKRAT
The muskrat is a rodent that usually eats

water plants, but also feeds on small
animals such as fish, frogs, and
freshwater shellfish.

Muskrat swims RUddy dUCK
powerfully with its webbed The ruddy duck is found in
back feet and uses its long, open waters in many parts of
hairless tail as a rudder Europe. It has a stiff, upward-
for steering. pointing tail and dives in search
of plants, small water insects,
GIANT oTTER
The largest member of the otter family larvae, and worms.
lives in South America. The giant otter
grows to more than 5 ft (1.5 m) long FALSE MAp
including its tail. It hunts catfish, TURTLE
piranha, and other fish. Unlike one of the
other otters, the giant otter pIKE many water
The northern creatures that
prefers to stay in streams pike is a large, suffer from
and pools and is not fearsome predator pollution of rivers and
often seen on land. with a huge mouth and lakes is the false map turtle
sharp teeth for seizing many from North America, shown
Today, this otter kinds of fish, as well as frogs, water birds, here. The harmful chemical
is very rare and small mammals. pike live in lakes and slow-moving waste that we pour into the
and is on the rivers; the biggest pike grow to more than 3 ft (1 m) long. water has also reduced this turtle’s food
of snails and shellfish.
official list of RIvER pLANTS
endangered Pond weed is food
species. for many different
lake and river fish.
The speed of the water in a river has a great effect on the
wildlife. In a fast river, the water sweeps the river bed clean of
sand and mud, leaving only pebbles. Nothing can grow
in the middle of a river, and the riverbank
consists mainly of plants, such as willows,
that hang over the water. In a slow
river, sand and mud can settle,
and plants such as irises take
root more easily.

CRAyFISH
The crayfish, found in rivers, is a freshwater
relative of saltwater lobsters. It is active mainly at
night and walks along the riverbed on its four
pairs of legs, eating a wide range of food, from
plant matter to worms, shellfish, and small fish.

307

LAKE AND RIVER WILDLIFE

Cattail lake WilDlife Heron
grows
to 8 ft trees such as willows and alders Many kinds of herons
(2.5 m) line the edge of many lakes; visit lakes and rivers all
high. rushes, tussock sedges, over the world. Herons
wade slowly in shallow
reeds, and other WilloW water, at times standing
marshy plants grow the willow tree perfectly still for several
closer to the water. plants thrives in the damp minutes, then suddenly
such as water lilies and water soil of riverbanks, strike at a frog or a fish
and the shores with their long, spear-
horsetails grow in the of lakes. its long,
shallow water, and stick penetrating roots shaped
up above the surface. help strengthen bills.
each type of plant is
the bank.
food for a different
assortment of animals.

MoorHen Dragonflies are a familiar
During the breeding season the male and sight around lakes and
rivers during the summer
female moorhen build a nest among months.
the vegetation at the water’s edge, Water lilies
and the female lays up to 11 there are about 200 kinds of water lilies.
eggs. the moorhen’s long, their leaves and flowers float on the
splayed toes enable it to walk surface of the water, and their long stems
on floating leaves stretch down about 6 ft (2 m) to the roots
on rivers, lakes, embedded in the mud below.
and marshes.
these birds eat
pond weeds,
fruit, and
sometimes
insects.

Water boatMan Water snake
this aquatic insect uses its paddlelike legs Many snakes can swim; the water snake
to row across the surface of the water. the is an expert swimmer. it glides across the
back swimmer, a similar creature, swims
upside down, often near the surface. lake with hardly a ripple. Water snakes
prey on small mammals, frogs, fish,
and small water birds, and their eggs
and nestlings.

Diving beetles breathe by trapping air
under the hard wing cases that
cover the body.

Insect larvae, fish fry Mirror carp
(young), and other small carp are fish that live in slow-flowing
creatures shelter among the rivers and weed-filled lakes. Mirror
plants along the water’s edge. carp are so named because their
bodies are covered with large, shiny,
mirrorlike scales. Mirror carp
search the river bottom for small
plants, shellfish, and worms.

Conservation Diving
the axolotl, shown here, is a kind of Mexican beetle
salamander. it cannot survive on land and is found the diving beetle
only in lakes such as lake Xochimilco, Mexico. like is a fierce predator. it
many other lake and river creatures, the axolotl is hunts tadpoles, small fish,
threatened by pollution. thousands of lakes in the water worms, and insects.
world are now lifeless because of the damaging
substances that flow into them. today, many lakes Find out more
and rivers are being turned into nature reserves in animal senses
order to protect the birds, fish, mammals, and other
wildlife they contain. birds
fish
Axolotl means “water beast.” frogs and other amphibians
snakes
308

Lakes

WateR fRoM RiVeRs, MoUntain spRings, and rain fills hollows in
the ground and forms lakes, which are areas of water surrounded by land.
lakes also form in depressions dug out of the ground by glaciers, or in
holes in limestone rocks. some lakes are artificial: reservoirs are lakes
made by building dams across rivers. several landlocked seas, such as the
caspian sea and the Dead sea, are really lakes. the caspian sea, which
lies between europe and asia, is the world’s biggest lake. its surface
covers an area almost as large as Japan.
lakes sustain a wealth of plant and animal life and are often
surrounded by fertile land. freshwater lakes provide water for
towns and cities, and recreation areas for swimming, sailing, and salty lakes
waterskiing. large lakes, such as the great lakes in north america, salt collects in lakes that have no outlet,
such as the Dead sea between israel and
Jordan. the water is so salty that people
are used to transport goods in ships. can float in it without swimming.
However, lakes do not
last forever. silt and
plants can fill up a
lake over a period Volcanic lakes
Rainwater fills the volcanic
crater at the summit of
of years and turn Mount Mazama, oregon,
it into a swamp. to form crater lake. it is
1,932 ft (589 m) deep,
making it the deepest lake
The great lakes are all linked to in the United states.
each other, and also to the
Atlantic Ocean by the Saint
Lawrence seaway.

kinDs of lakes
lakes form in hollows dug by glaciers during the ice age, and in places
where glaciers have left barriers of rock across valleys. Water dissolves huge
holes in limestone regions, which often fill with rainwater to create lakes.
lakes can also form in volcanic craters.
Plants grow on
the damp,
fResHWateR lakes fertile soil.
the water in freshwater lakes is not
salty like the sea, because the lakes are
constantly fed and drained by rivers.
the largest group of freshwater lakes are
the great lakes in the United states and canada.
lake superior (left) is the largest of the great lakes.

tHe life of a lake 3 Dying lake
the soil
lakes are not permanent features of the landscape. layers extend
they may come and go as their water supply into the lake.
rises and falls. lakes can slowly fill with plants grow and
soil and stones washed down from the the layers
land above the lake. the outlet river become land.
may deepen and drain the lake. this continues
until the lake
River flows vanishes.
into lake.

sWaMps anD 1yoUng River 2 sHRinking Soil and mud build up at
MaRsHes lake drains lake. lake sides and bottom of lake.
a river fills a hollow the river carries soil,
the everglades is a large in the ground to create which falls to the Find out more
region of swamps in florida. the lake. the water bottom as it enters the Dams
swamps, or marshes, can flows through the lake, lake. a layer of soil
form at the edge of a lake running out into builds up along the glaciers and ice caps
where the ground is soaked another river. edge of the lake. lake and river wildlife
with water or covered with Marsh and swamp wildlife
shallow water. they also
form on land where water Rivers
cannot drain away. Water

309

Languages

THe aBiliTY To TalK is one of the skills that makes humans different
from the rest of the animal world. although some animals communicate
with gestures, such as mating displays, human speech is much more highly
developed. in english, for example, most people use a vocabulary (a list of
words) of about 5,000 words in talking, and 10,000 in writing. a language
is a way of organizing spoken sounds to express ideas. Human language
developed over thousands of years, and people in different countries use
different languages. some languages share words with the languages of
nearby countries. for instance, book is libro in both italian and spanish,
and livre in french; in english we get the word library from the same
source. There are now some 7,100 different languages
Tower of BaBel and many dialects—local versions of major languages. More than half of
at the beginning of this China’s 1.3 billion
Bible story, everyone spoke population speak
the same language. But English is spoken Mandarin Chinese.
when people tried to build worldwide by more
a tower to reach Heaven, than one billion
God became angry. He people, many
made many languages so as a second
that people could not or third
understand and help language.
one another.

France once There are
ruled many at least 780
countries in languages in India.
Hindi and English
West Africa, and are the official
people there still languages.

speak French as
well as their local
languages.

Some people have no difficulty in
learning foreign languages and
can speak several fluently.

There are about 800
languages in Papua
Common lanGuaGes New Guinea.

a map of national languages shows how Mandarin Chinese
european nations have spread around the
world: for example, english settlers took their
laTin language to the united states, Canada, australia, English
for many centuries, educated
people of many nationalities spoke and new Zealand. spain conquered much of south
latin as well as their native, or first, america, and spanish is still spoken there. But many Russian
language. Throughout europe,
scholars, governments, and the people using these languages also have their own
Church used latin. local language, which is part of their native culture.
Spanish
Sign language
Human speech and s PeaK French
hearing make language
possible. People who have Portuguese
difficulty speaking or
hearing cannot use a Arabic
spoken language. instead,
they communicate using Other
hand signals. There are
signs and gestures for all Find out more
the common words, and alphabets
signs for individual letters. movies

writers and poets

310

law

romAN lAw No society could exist without rules that define a person’s
the romans developed the most
complete system of laws in the rights and obligations. law is the set of rules by which a society is governed.
ancient world. By the 6th century every country has its own legal system. the American legal system has its
ce, roman emperor Justinian i roots in the common law practices of england, so called because the law
(shown on the coin above) had applied to everybody. common law systems are based upon legal precedents,
collected the laws of the empire or earlier court rulings on similar cases. there are two separate levels of
together into a comprehensive courts in the united states—state and federal—to try cases involving either
code that is still influential today. state or federal laws. there are also two types of law—civil and public. civil
laws govern disputes between two parties, while public law relates to a
person’s obligations as a citizen. Known as the “law of laws,” the constitution
is the ultimate law in America—it has force over all other national and state
laws, and contains conditions that all laws must meet.

civil lAw

civil law cases concern people’s rights and responsibilities in their
relations with other people. some of the matters dealt with by civil
law include property ownership, marriage and divorce, adoption
and child support, contracts and other business agreements, and
wills and inheritance. if a person feels their
civil-law rights have been violated in some
way, they may file a civil suit, or lawsuit, in
court (left). the court will decide whether
any amends should be made. typical civil
law cases involve landlord and tenant
disagreements, child custody disputes,
insurance claims, traffic accidents, and
medical malpractice.

Justice for All The police enforce
statues representing justice wear a blindfold to show that criminal law, which is a
all people are entitled to equal treatment under the law, part of public law. This
regardless of their social status, class, or race. the scales
show that justice—through the law—weighs opposing officer is issuing a
evidence like a balance weighs goods. the sword speeding ticket.
represents swift punishment for the guilty. however,
sometimes not all law is fair, as governments can make
laws that remove freedoms, as well as safeguard them.

A figure representing The courthouse and jail in
justice holds the scales. Marietta Ohio, were built in 1798.

history of AmericAN lAw PuBlic lAw
colonial American lawyers used
english law books and english court A person’s rights and duties as
rules. After independence, American law a member of a community, and as a
rapidly outgrew its english roots, especially citizen, are established by public law.
property and business law. common law remained at
the core of the us legal system, and was followed its branches include: criminal law,
in every state except louisiana. louisiana which defines crimes and rules for
was originally colonized by the french,
which meant that french law codes were arrest, trial, and punishment;
practiced there for many years. constitutional law, which relates to

the rights and responsibilities set
forth by the constitution;

administrative law, which deals with
the day-to-day workings of the

government; and international law,
which concerns agreements between

countries. in a public law court, the
government tries a person who has

committed a specific crime.

311

LAW

A 1950s jury hears
a murder case.

O.J. Simpson was Trial by jury
tried in a famous
televised case. a jury is a group of people chosen to decide the truth
from the evidence given in a court of law. although each
Trial by Television
Many states allow television to film court state has its own qualifications for jury service, the
cases. in recent years, television coverage of people chosen to hear the case must be unbiased. in a
sensational, high-profile trials—such as those trial, the evidence is presented to the jury by lawyers for
of Michael jackson and o.j. simpson—has
drawn huge audiences. some people believe the prosecution and for the defense. The jury then
that the cameras undermine justice, because reviews the evidence. lawyers may call witnesses to testify
the publicity draws attention away from the
facts of the case and influences the jury. and answer questions about the facts of the case. The
others argue that allowing trials to be televised judge makes a charge to the jury—a statement of the
safeguards the public’s right to be informed. rules of law that apply to the particular case. The jury
The first us leaves the courtroom to discuss the charge until they
attorney general
was edmund reach an agreement on the verdict.
randolph.
ChallenGinG The law
The courts in america have the power of judicial review,
which means they can throw out any laws that do not agree
with the united states Constitution, or individual state
constitutions. This power was established in a famous

supreme Court case of 1803, Marbury v. Madison. in this
decision, Chief justice john Marshall (left) ruled for the
first time that an act of Congress
was unconstitutional. This case
set a precedent that allowed
other acts of Congress to
be challenged.

InternatIonal law
even though all nations do not share
the same legal systems, they cooperate
under the rules of international law.
These laws are made with the consent
of two or more countries.
international law deals with crimes
like hijacking and terrorist acts, such
as the september 11th attacks.
Many countries share extradition
treaties so that accused people
can be returned to the country
where they committed a crime
if they are captured elsewhere.

juDGes
a public official, called a judge, presides
over all trials. judges have to be lawyers

because they apply the rules of law to
court cases. The judge is responsible for

ensuring a fair trial, and decides the
punishment if the accused is found guilty.

lawyers Find out more
a lawyer is licensed to represent people in court Constitution
or give them advice in matters of law. learning Government and politics
to become a lawyer takes several years, and most human rights
states require people to pass a special test called supreme court
a bar exam before they are allowed to practice law.

312

Leonardo da vinci

a hiGhLY taLenteD artist and scientist, Leonardo
da Vinci was years ahead of his time. he was one of the
greatest figures in the movement called the renaissance,
the revival of art and learning that began in italy in the
15th century. today, many people remember Leonardo
for painting some of the most famous pictures of his time,
1452 Born near the but he achieved a great deal more than this. he designed
village of Vinci, in italy. castles and weaponry, invented machines, studied physics
1466 moves to Florence; and mathematics, and made accurate scientific drawings
works in studio of the of plants, animals, and the human body. he was probably
artist Verrochio. one of the world’s greatest all-around geniuses. mona lisa
1482 Works as architect, Leonardo’s best-known
engineer, and painter in portrait is of mona Lisa, the
milan, in northern italy. wife of a rich Florentine.
1503 Begins mona lisa. the painting is famous for
1503 Designs famous mona Lisa’s haunting smile,
flying machine. and for the softly blended
1513 makes pioneering colors, an effect known as
study of lenses and optics. sfumato. the painting is in
1515 studies anatomy. the Louvre Gallery in Paris.
1516 Dies in France.
renaissance man
machinerY
in Leonardo’s time, it was
Leonardo’s notebooks are still possible for a person
crammed with designs for to become skilled in many
ingenious machines. some different branches of
of these devices, such as a
pump, an armored car, and a learning—such a person was
machine for grinding lenses, called a “renaissance man.”
could actually have been Leonardo produced new
built and used. Others, like ideas in practically every area
his famous “ornithopter” he studied. he wrote down
flying machine with its many of these ideas in a
flapping wings, would never series of beautifully
have worked, but they were illustrated notebooks.
still ahead of their time.

Tank design architecture
Buildings and town planning
Flying machine fascinated Leonardo. he designed
anatOmY an “ideal city” that was never
built. the streets of the city were
in the 16th century, people knew arranged in a grid pattern, like a
little about anatomy (the study modern american town. he also
of the human body and how it designed bathhouses, together with
drainage networks, and systems for
works). Leonardo was one of the garbage collecting, which were
first to dissect, or cut up, dead
bodies and draw them, unknown at the time.
sketching every muscle and
bone in detail. if his drawings Find out more
helicopters
had been published, they would
have proved helpful to doctors Painting
and other scientists. rensaissance

313

lewis and clark

iN 1803, PReSideNT THOMAS JeffeRSON sent
Meriwether lewis and William Clark to lead an expedition to
explore the wild and largely unknown lands west of Missouri,
to the Pacific Ocean. Their instructions were to explore
and chart the region, to make contact with Native
Americans, and to find out if there was a water link
between the Atlantic and Pacific oceans. lewis and Clark
were not experienced explorers, but they successfully led
a band of about 40 men, traveling by boat, horse, and foot,
some hazardous 8,000 miles (13,000 km) to the Pacific
and back. They returned home as heroes with important
and exciting new information about the region, which WilliAM ClARk
later encouraged US expansion westward. Clark (1770-1838) was a lieutenant

in the army. He resigned in 1796,
but rejoined the army in 1804 to
MeRiWeTHeR leWiS SACAJAWeA go westward with lewis. Although
lewis (1774-1809) was private untrained, he mapped accurate
secretary to President Jefferson. lewis and Clark encountered many Native Americans on their journey. routes for the expedition and
Co-leader of the expedition, None was as important as Sacajawea (1786-1812), also known assembled records of the journey
he served as the party’s as “Bird Woman.” She joined the expedition in 1805, and for publication.
naturalist, collecting animal guided the explorers over mountain trails. Her
and plant specimens. presence encouraged friendly relations
with the Native Americans.

Pacific Columbia River Lake
Ocean Superior

Cascades Rocky Mountains Mississippi River
Missouri River

Saint Louis

ROUTe Of THe exPediTiON
The expedition left Saint louis on May 14, 1804,
traveling along the Missouri River by boat. in
November, the explorers reached what is now
North dakota, where they spent the winter with
native Mandans. in April 1805, they continued up
the Missouri. leaving the river, they struggled on a
perilous journey over the Rocky Mountains, then Wildlife
paddled up the Columbia BOATS The expedition returned with
River, finally reaching the The expedition set sail for the
Pacific in November. They valuable samples of animals,
spent the winter on the Pacific Ocean in a flat-bottomed plants, rocks, and minerals.
Pacific coast, before keelboat and two smaller “pirogues,”
retracing their steps, or dug-out canoes similar to those lewis became particularly
used by Native Americans. in interested in grizzly bears,
rough water, the travelers
arriving back in St. louis were forced to tow one of which tried to
on September 23, 1806. the boats from land attack him. He reported a
or carry them large number of grizzlies,
around rapids.
which pleased President
Early settlers traveled WeSTWARd exPANSiON Jefferson, who was eager
across North America to develop the fur trade
in a covered wagon. lewis and Clark’s expedition proved there
was no direct water link between the Atlantic in the United States.
and Pacific oceans. However, lewis and Grizzly bear
Clark’s information about the diversity and
richness of the lands attracted hundreds Find out more
of traders and settlers to the West. from Bears and pandas
the 1840s, increasing numbers made their Mountain wildlife
way on the long journey westward in covered Native americans
wagons, or “prairie schooners.” United states of america
United states, history of

314

Light

Without light, life on Earth would fluorEScENt light
Most modern light bulbs are fluorescent tubes like this one.
be impossible. Sunlight provides the When an electric current is passed through the gas in the tube,
energy to make plants grow and keep
all living things alive. light itself is gas atoms emit invisible, ultraviolet light. the ultraviolet light
a form of energy that travels as tiny strikes phosphors—chemicals in the tube’s lining—and makes
packets of electromagnetic energy them glow with a bright white light.
called photons. When photons
enter our eyes, they stimulate Electrical contact is made
special light-sensitive cells so that when the bulb terminal is
we can see. other forms of energy screwed into the socket.
that travel as electromagnetic The electronics
waves include radio waves, x-rays, hidden inside the
and microwaves in microwave white plastic base
ovens. Just as there is a spectrum control the light.
of colors in light, there is also
an electromagnetic spectrum. Inside a glass tube, The explosion
in fact, light waves are also a type an electric current of gunpowder
of electromagnetic wave, and the flows through a gas inside a firework
colors in light form a small part of (mercury vapor) produces a burst
the electromagnetic spectrum. light making it emit of colored light.
waves, and all other electromagnetic invisible ultra-violet
waves, travel at 186,000 miles (UV) light.
(300,000 km) per second, which is A chemical coating
so fast that they could circle the world inside the bulb
almost eight times in a second. Nothing converts the UV
in the universe can travel faster than light. light into visible
white light.

Nuclear reactions inside the center
of the sun produce intense heat
and light. All stars produce light
from nuclear reactions.

brightNESS of light Some deep-sea fish Searchlights
have luminescent give out very
the farther you are from a light, the less bright it will stripes and spots intense light, often
seem. this is because light spreads out in all directions along their bodies produced by an
that give out light. electric spark
from its source. So when you are far away, the light is between two
spread over a wide area. Many stars, for instance, Candles and pieces of carbon.
are much brighter than our sun, but their lanterns give
light is spread out over so vast an area out light. SourcES of light
that by the time it reaches us, the When things burn,
stars do not even seem as they give out light Many different objects give
bright as a candle. as well as heat. off light. the sun, traditional

Shine a flashlight A candle is a wide electric light bulbs, and
on a wall and source of light, so it fireworks are incandescent,
watch the pool of produces a fuzzy
light grow larger shadow. which means they glow
and dimmer as because they are hot. but not
you move the all lights are hot. chemicals,
flashlight not heat, produce the glowing
further away.
spots on the bodies of some
deep-sea fish. all cool lights,
including fluorescent lights,

are called luminescent.

light aNd ShadoW Current flowing iNcaNdEScENt light bulb
light travels in straight lines, so, through metal in the middle of an incandescent electric
in most cases, it cannot go around light bulb is a tiny spiral of tungsten wire
obstacles in its path. When light rays filament makes it called the filament. When an electric
hit a solid object, some bounce back glow white-hot. current is sent through the filament, it
and some are absorbed by the object, warms up so much that it glows white-
warming it up a little. the area behind hot. it is the brightly glowing filament
receives no light rays and is left in shadow. that produces light.

315

light

Convex mirror Convex Mirrors
produces images Mirror
smaller than Mirrors that bulge Light passes easily through
the object. outward are called transparent substances, such
Concave convex mirrors. as glass and water, but not
mirror Their curved shape through opaque objects,
produces a reflects light from such as paper. Most opaque
magnified a wide angle, giving a much wider view objects have a rough surface
image. than a regular mirror does. This has the that scatters light in all
effect of making all objects look small. directions. However, a
mirror has a smooth surface,
PLane so it reflects light in a regular
Mirror way. When you look at your
With a plane, face in a mirror, the light
or flat, mirror, bounces straight back,
the reflection is producing a sharp image.
exactly the same Most mirrors are made of
size as the object, glass; your face is reflected
but the left and right are reversed. With from a shiny metal coating
both curved and plane mirrors, the at the back of the mirror,
reflection appears as though it were not from the glass.
behind the mirror.
A flat mirror produces
an image the same
size as the object.

ConCave Mirror Lenses anD reFraCTion
a concave mirror, which is curved Glasses, cameras,
inward, forms two kinds of images. telescopes, and
if the object is close to the mirror, the microscopes use lenses to
reflection is larger than the real thing. create particular kinds of
if the object is far away, the image images. The lenses in a
formed is small and upside down. telescope, for example, ConCave Lens
produce a magnified view a concave lens is thicker at the
Rays travel in straight of a distant object. all edges than in the center, so it
lines in cool air lenses work on the spreads light rays out. if you look
principle that although through a concave lens, everything
light always travels in appears smaller.

Focus

straight lines, it travels
Upside- Rays are bent slower through glass than
down image as they pass through air. if a light ray
forms through layer strikes glass at an angle,
of warm air one side of the ray will hit
the glass just before the Convex Lens
MiraGe other, and will slow down Convex lenses bring light rays
in the hot desert, weary travelers are often fooled by the sight of an oasis. earlier. The effect is to together. at the focus, where light
The oasis appears on the horizon, only to vanish as the travelers hurry bend the light ray slightly, rays from a distant object meet, they
toward it. What they have seen is an illusion called a mirage. in the example just as a car pulls to one form an image of the object that
above, light rays traveling from the palm tree are bent upward by the warm can be seen on a screen.
air. The observer’s eyes interpret the light as having traveled in a straight
line, so he or she sees a watery reflection of the tree on the ground. side if it has a flat tire.

This bending of light
is called refraction.
Fiber optics Magnifying
Fiber optic cables are channels that carry light. They glasses are
are flexible, so they can carry light around corners. convex lenses.
The fibers are long, thin filaments of glass; the light
bounces back and forth along the inner surface of the Light refracts when it passes
glass. Fiber optics are valuable for seeing into awkward through water, because the water
places. Doctors can use fiber-optic endoscopes to see slows it down. This makes objects
inside a patient’s body without opening the body up. look as though they are bent.

Find out more
Cameras
Color
eyes

Photography
Physics
Plants
sun

316

L AbrAhAm

incoLn

one of The moST famoUS pReSidenTS
in US history is abraham Lincoln. But when he
was elected in 1860, less than half the country
supported him, and he remained very unpopular
with many people for the entire five years of his
presidency. Lincoln did not approve of slavery,
and many landowners in the Southern United
States still kept slaves. as a result of his election, LincoLn’S BiRThpLace
11 southern states left the Union and declared This log cabin in Kentucky is a
1809 Born in Kentucky. themselves an independent confederacy, or replica of the birthplace of
1831 moves to new Salem, alliance. civil war then broke out between the
illinois, where he works abraham Lincoln. The poverty
as a storekeeper, surveyor, of Lincoln’s childhood influenced
and postmaster while
studying law. his political ideas.
1834 elected to state
legislature. Union and the confederacy. Lincoln was a capable
1836 Qualifies as a lawyer. war leader. he struggled to keep the remaining states united under his
1842 marries mary Todd. leadership. many people in his own government opposed him. But in 1865,
1846 elected to congress. he led the Union states to victory. afterward, Lincoln tried to repair the
1855, 1859 Runs un- damage done by the war and bring together the two opposing sides.
successfully for Senate.
1860 elected president. GeTTySBURG addReSS
1861 mobilizes 75,000 abraham Lincoln was famous
volunteers to put down the for his speeches. in 1863, he
southern rebellion. attended the dedication of
1863 issues emancipation a national cemetery on
proclamation. the site of the civil War
1864 Re-elected president. battlefield in Gettysburg,
1865 assassinated. pennsylvania. he made
a speech known as the
Gettysburg address.
he hoped that “these
dead shall not have
died in vain.”

abolition The deaTh of LincoLn
The move to abolish slavery on april 14, 1865, abraham Lincoln was watching a play at
in the United States grew under ford’s Theatre in Washington, d.c. John Wilkes Booth, an
Lincoln. Led by white middle-
class northerners, many freed actor who supported the Southern states in the civil War,
slaves joined the abolition crept quietly into the president’s box and shot him. The
movement. some, such as
andrew Scott (right), fought president died from his wounds the next day.
in the Union army during moUnT RUShmoRe
the civil War. Slaves fled The faces of four american
presidents—George Washington,
from South to north Thomas Jefferson, Theodore
(and freedom) via the Roosevelt, and abraham Lincoln—
Underground Railroad—a are carved out of rock on the
side of mount Rushmore in the
secret escape route. Black hills of South dakota.
harriet Tubman, a famous
pioneer of the railroad, helped Find out more
abolitionist movement
300 slaves escape in this way.
civil war
Slavery
Tubman, harriet
United states, history of

317

LIONS,

tIgerS, aND OtHer BIg CatS

Few creatureS are HeLd in such awe as
lions, tigers, cheetahs, and leopards, which we
often call the big cats. these agile predators
have strong, razor-sharp teeth and claws,
muscular bodies, and excellent senses.
cubS their beautiful striped and spotted
Like all young big cats, tiger cubs fur breaks up their outline and
have pale markings when they are camouflages them, allowing them
born. after a few months, the pale to ambush unwary zebras, giraffes, and
stripes change to black and orange.

other prey. there are seven kinds of big cats. the tiger is the largest.
a fully grown tiger may measure more than 10 ft (3 m) from nose to
tail; a fully grown lion is almost as big.
the first large cats lived 45 million years ago. Many, including Hunting prey
the lion, cheetah, and leopard, still inhabit parts of africa. Lions live mainly on savannas (grassy
Snow leopards and lions dwell in the mountains and plains) and scrubland, and the females
forests of asia. Jaguars are the largest of the big cats do most of the hunting. this picture
in north and South america. they are equally at shows two adult lionesses charging at

a young gazelle, separating it from
the rest of the herd.

home swimming in lakes or climbing trees.

Lion has a Lion pride
thick, shaggy Lions are the
mane. only big cats
that live in
groups, called
prides, which may be
up to 30 strong. the pride roams
over an area of 40 sq miles (100 sq km) or more,
depending on the abundance of prey in the area.
the large male lions protect the pride’s territory
against other prides. the lions also defend the
females against other males.

SkuLL and teetH
Lions and other big cats have short,
strong skulls with powerful jaws.
their spearlike canine teeth
are used to grab hold of the
victim. the large molar teeth
cut flesh and gristle as the jaw
opens and closes.

Large, strong
canine teeth for
tearing prey

The dominant male is Large feet and
the strongest member sharp claws
of the pride. It can
measure 8 ft (2.5 m) in carnivoreS
length, and 3 ft (1 m) Lions, tigers, and other big cats are true
high at the shoulder. carnivores (meat-eaters). Lions usually eat large
prey such as antelopes and zebras. one giraffe
is often enough to feed a whole pride of lions.

lions, tigers, and other big cats

Claws out leopard
when a cat pounces the leopard weighs about 130 lb (60 kg),
on a victim, or climbs and its body measures about 5 ft (1.5 m).
up into a tree, it leopards are adaptable creatures. they
unsheathes its sharp can survive in hot tropical forests or on
claws. Muscles in the cold mountainsides. they may
feet extend the claws also live close to towns
and draw them back in.
and villages.

Claws in
Most of the time, a cat’s claws
are protected in muscular sheaths.
this keeps the claws sharp and less
likely to break. some cats, such as
cheetahs, don’t have sheaths and so
their claws are visible all the time.

CliMbing
leopards are excellent
climbers. they sleep, rest,
and watch for prey from the
branches of trees. they also drag their
uneaten food up into a tree to store it,
and to keep it away from scavengers.

panther
the black panther (right)

is a leopard with dark
coloring. in daylight, its
spots show black in its

dark gray-brown fur.

tiger Jaguar roaring
the jaguar (below) stalks its prey in the only the big
unlike most cats, the tiger does not mind water. same way as the tiger. Jaguars eat a variety cats—lion, tiger,
a tiger sometimes pulls its dead prey near the of creatures, including tapirs, fish, frogs, jaguar, and leopard—can roar, and
water’s edge, because it needs to take frequent rodents, sloths, and small caimans (south they do so loudly. the snow leopard
drinks during a meal. tigers stalk their prey american crocodilians). is the only big cat that cannot roar.
through dense undergrowth, then bound over the males roar to warn others to
the last 50 ft (15 m) or so, taking their victim 37 mph keep away from their territories.
by surprise. on average, a tiger consumes a lion’s roar can be heard up
about 40 lb (18 kg) of meat a day. to 5 miles (8 km) away.

Cheetah Asia Conservation

Cheetahs hunt by sight rather Asia leopards and other big cats have
than smell, and once it spots its been overhunted for their fur and
Africa Tigers because they attack livestock
prey, no animal can outrun a Lions and, very rarely, people. the
cheetah over a short distance. Asia Asia trade in big cats and fur products
Africa is now banned by an international
Cheetahs can speed along at Cheetahs agreement. the maps show the
about 37 mph (60 km/h)—as main areas of the world where
fast as a car. since the cheetah’s these big cats still live.
claws are always extended, they
provide the cheetah with extra Africa Find out more
Leopards animals
grip as it starts its run. if a
stalking cheetah is detected animal senses
before it gets within about 600 ft Camouflage, animal

(180 m) of its prey, it does Cats
not make the final dash. Conservation

Cheetah and endangered species

Mammals
Zoos

319

Literature

lItERatuRE IncludES PlaYS, poems, novels, and short stories. It is
writing that carries strong and lasting value through offering the reader
important insights into the nature of human emotions. For example, the
English playwright William Shakespeare (1564-1616) often based his plays
on old or well-known stories, and because Shakespeare was a very skilled
writer and had a great understanding of human nature, his plays still
excite audiences of all nationalities hundreds of years after they were
written. literature can be powerful, as it can express the writer’s
thoughts, ideals, and beliefs. authors, or writers, have often used
Gulliver’s Travels literature to protest injustice in the world, make a social criticism, and
influence the opinions of peoples or governments. For instance, in The
English author Jonathan Swift Grapes of Wrath, american novelist John Steinbeck (1902-68) drew public
(1667-1745) wrote Gulliver’s
Travels in 1726. although he did
not write the book for children, attention to the suffering of homeless farmers fleeing from oklahoma
the first two parts have long been to california during the Great depression of the 1930s.
popular with young people.

When the people of Lilliput find
Gulliver sleeping in their land, they tie
him down on the ground so that he
cannot move.

Plot The arrogant and petty-minded
Lilliputians represent the ruling
the collection of events that class of 18th-century England.
occur in a work of literature is cHaRactERS
called the plot. Gulliver’s Travels tells the an essential part of most literature is the
story of lemuel Gulliver, a ship’s surgeon. writer’s description of the characters—the
In the first part, Gulliver is shipwrecked in people who take part in the plot. a writer
an imaginary land called lilliput, where the portrays a character’s personality by
people are only a couple of inches tall. In the describing how they react to events in the
second tale, he meets the giants of Brobdingnag. story. For example, Swift shows that Gulliver
In the third story, Gulliver visits various strange is a kindhearted man by describing how he
lands. Finally, he is marooned among the entertains the tiny lilliputian people: “I
Houyhnhnms—a race of horses that are wiser would sometimes lie down, and let five
and more intelligent than their repulsive human or six of them dance on my Hand.
servants, the Yahoos. Rejected by the Houyhnhnms, and at last the Boys and Girls
Gulliver returns to England, where he is no longer would venture to come and play
able to tolerate the company at Hide and Seek in my Hair.”
of other humans.

Gulliver is visited by
a Lilliputian noble.

tHEmE oRal lItERatuRE
Writers use their long before writing was
plots and characters to invented, storytelling, or oral
explore key themes, such as literature, was used to pass on myths
love, death, morality, and social or and history. the heroine of a traditional
political issues. Gulliver’s Travels seems like just arabic story called One Thousand and One
an adventure story, but the underlying theme is Nights is a storyteller named Scheherazade (right). Her
18th-century England, where the lilliputians and cruel husband vows to kill her in the morning, but she
other nationalities represent different types of charms him with a tale and so delays her death. Each
people with their good and bad qualities. night she tells another story and lives for one more day.
after many stories, her husband changes his mind
and spares Scheherazade’s life.

320

Literature
ePics ANd sAgAs
epics and sagas tell of legendary heroes
and their deeds. An epic tells the story
as a long poem, while a saga is written
in prose. The national Persian epic, the
Book of Kings (Shah-nameh) by Firdausi
(c.935-1020), is 1,000 years old, and
tells the story of Persian kings and their
battles against monsters in mythical
times. other great epics include
Homer’s Iliad and Odyssey; virgil’s Aeneid;
Beowulf, a 10th-century epic written in
old english; and John Milton’s Paradise
Lost and Paradise Regained.

This copy of the Book of Kings BiogrAPHy
is written in Arabic script. A biography is a book that describes a
person’s life. in an autobiography the
PoeTry author writes of his or her own life. Us
writer Mark Twain (right) was portrayed
Poetry uses devices, such as in J. Kaplan’s biography Mr. Clemens and
rhythm and rhyme, to focus Mark Twain (the title refers to Twain’s
real name, samuel langhorne clemens).
attention on the words.
rhythm is the use of sound Novels
patterns, such as repeated
accents or beats, to make A novel is a long (invented) story, written in prose.
This form of writing only began in the early 17th century,
a line flow. one of the
world’s greatest poets and has had a dramatic rise in popularity
was the American Walt because there are novels to suit all tastes.
Whitman (1810-92), some offer insights into everyday life, and
whose poems express a some tell of fantastic adventures that keep
great love of his country
you turning the pages. American author
and its people. His louisa May Alcott wrote Little Women
collection of poems
Leaves of Grass (1855) (1868-69), which tells the story of four
sisters and their lives. This
is considered one of remains one of the best-loved
his best works. children’s books ever
written. Many successful
modern authors are now
rewarded with high incomes
from sales of their books, as
well as from movies based
on their novels.

drAMA Louisa May Alcott

literature that is written to be performed by actors is called drama. sTories
different countries have their own forms of drama. There is little Most stories describe a single incident or events that
scenery in Japanese Noh drama (below), which was first performed take place over a short period of time. There are
in the 14th century. The all-male actors use dance, mime, and children’s stories about every subject ranging
masks for each performance, which can last for several hours. from adventures to ghosts. one of the best-
Noh drama is influenced by the religious beliefs of known story writers was the danish author
Buddhism and shintoism. Hans christian Andersen (1805-75),
who wrote tales such as The Emperor’s
Noh actors perform a program of New Clothes and The Ugly Duckling.
five plays, based on classical A Hans Christian Andersen story,
literature, romances, or The Princess and the Pea, tells
poetry, accompanied how a single pea beneath a heap
by a chorus with of mattresses keeps a princess
an orchestra of awake all night.
drums and flute.

Find out more
Alphabets
Movies
Theater

Writers and poets

321

LIZARDS Lizards can hear
through their ear
THE LARGEST GROUP of reptiles is the lizard family, with about 5,500
openings.
species. Lizards live in almost every habitat except the open sea and the
far north. The huge Komodo dragon is the largest, and tiny geckos are the
smallest—some are less than 1 in (2 cm) long. A typical lizard such as
the iguana has a slim body, a long tail, legs that splay out sideways,
and five-toed feet. There are many variations, however; skinks
are often extremely long, with short legs. They move
effortlessly through sandy soil with a wriggling motion.
Glass lizards are even more snakelike, most have no
legs and only a few species have small, stubby hind
legs. Several other kinds of lizards, including the
slowworm, have also lost their limbs during the
course of evolution. Like other reptiles, most
female lizards lay eggs, which they bury in

the soil or hide under rocks until
the young hatch.

Long tail
for balance

ASiAn wATER dRAGOn Typical scaly skin like Green iguana
other reptiles, such as Outstretched claws help
This lizard is found in Asia and lives mainly in trees snakes and crocodiles in gripping while climbing.
that grow close to water. Like most lizards, the water
dragon is able to swim. Unlike most other lizards, LizARd TAiLS
however, which move on all four legs, the Asian in the same way that a starfish regrows
water dragon runs on two legs if it is threatened,
which gives it more speed on land. its arms, a lizard can regrow its tail.
when a predator such as a bird or cat
Loose skin The more the frilled grabs a lizard by its tail, the lizard sheds
around neck lizard opens its
looks like a mouth, the more the tail in order to escape. The
huge collar. the frill expands. vertebrae (backbones) along the

Tail waves Tree skink has tail have cracks in them, so the
around to lost the end tail breaks off easily. The
frighten of its tail. broken-off part of the tail
enemy. often twitches for a few
minutes, confusing the
Tail has regrown enemy while the lizard
fully within a runs away. The tail
few months. grows back to its
original length in
about eight months.
Tokay gecko

FRiLLEd LizARd TOKAy
GEcKO
The Australian frilled The pads on
lizard has a flap of loose the feet of the
skin around its neck that tokay gecko are covered with about one
folds flat along the body. million microscopic hairlike structures
The lizard raises the frill to that help the gecko grip on to surfaces. in
make itself look bigger in order southeast Asia, where it lives, it can be seen
to scare away a predator. it also waves walking up glass surfaces and across ceilings.
its tail and head around to alarm its
enemy, and then scuttles away.

322

Five claws lizards Male anole lizard
on feet inflates its red
TegU LIzard throat sac.
The young tegu lizard shown left
is found in tropical areas of South
america. It feeds mostly on young
birds and mammals, and also eats
other lizards. Like most lizards,
the tegu has a tough, scaly skin,
a forked tongue, five claws on its
feet, and movable eyelids.
Forked
tongue

Komodo Komodo dragon anoLe LIzard
dragon lizards
feasting on the carcass The Komodo dragon is the anole lizards belong to the iguana family of
(dead body) of a deer largest lizard—up to 10 ft (3 m) lizards. There are many different kinds,
long. It scavenges on dead animals found in tropical areas of Central and
and also catches deer, pigs, and wild
boars. Komodo dragons are found only South america. anole lizards are territorial
on a few of the Lesser Sunda Islands, Indonesia. (they guard their territory). The males

inflate their red-colored throat sacs, which
they display to each other as a sign of

aggression. anole lizards are sometimes
called american chameleons.

gILa monSTer Gila monster feeding
on newborn mice.
only three lizards have a poisonous bite—the green geCKo
gila monster, the mexican beaded lizard, many lizards are
colored to blend in
and the Komodo dragon. The gila with their surroundings.
monster (right) is found in dry, Treeclimbing lizards
scrubby areas. It hides in a burrow such as this green gecko
by day and emerges at night to eat are often bright green
small animals such as mice, and the to match the leaves;
eggs of birds and other reptiles. desert-dwelling lizards
are sand-colored or brown.
Thorny devIL many kinds of chameleons
The extraordinary-looking thorny devil is also can change their color
called the moloch. Spines protect its body according to their surroundings.
from nose to tail. Thorny lizards live in dry
parts of australia, where they forage for ants.
when the young molochs hatch from their
eggs, they look like tiny,
spiny versions of
their parents.

IgUana After each dive,
Like all lizards, iguanas depend on heat Galapagos marine
iguanas sunbathe
from the environment to keep their on the rocks to
bodies warm and active. They spend much warm up again.
of the day basking in the sun, absorbing its
Slowworms grow
warmth to prepare for activity. at night to about 20 in
they become slow and sluggish as their body
(50 cm) in length.
temperature falls. The galapagos marine
iguanas shown here dive to more than 35 ft Find out more
(11 m) deep into the sea in search of seaweed. Camouflage, animal

SLowworm desert wildlife
The slowworm is not really a worm, but a lizard. It is not slow reptiles
either; when disturbed, slowworms can wriggle away rapidly to Snakes

safety. Slowworms are found in fields and scrubland in
europe, northern africa, and southwestern asia. They feed

on slugs, spiders, and insects. Unlike most lizards,
slowworms give birth to fully formed young.

323

low countries

Small and denSely populated, the low The low Countries lie in northwest
europe, with Germany to the east
Countries are highly developed industrial nations and France to the south. To the
with thriving economies. nearly one-third of the west lies the north Sea.
netherlands lies below sea level. Over the last four
BulB FIeldS centuries, dutch engineers have reclaimed land
The dutch have been famous for by pushing back the north Sea with a network of
their flower bulbs since the 16th barriers, or dikes. In northern Belgium, the land
century, when tulips first arrived is also flat and low-lying, although to the south it
in europe from the middle east. rises toward the forested uplands of the ardennes.
In the spring, fields of spring flowers Belgium only became independent in the
are a spectacular sight. Fresh-cut 19th century. It is divided by language; dutch
flowers are flown all over the world. (Flemish) is spoken in the north, while French
is spoken in the south. Farming is important
throughout the region. The fertile land and cool,
rainy climate is ideally suited to dairy and crop
farming. major industries produce iron and steel,
natural gas, clothing, textiles, and electrical
goods. The tiny country of luxembourg has
the highest living standards in europe, and
is known as a major banking center.

amSTerdam
a city of 90 islands connected by 1,300
bridges, amsterdam is linked by canal to
the north Sea. The city became important
in the middle ages, and many of the
churches, towers, and gabled merchants’
houses of the old city still stand today.
In the 17th century, amsterdam was the
financial capital of the world. Since 1945,
new suburbs have been built on polders luxemBOurG
(reclaimed land), tripling the size of the city. The capital of luxembourg stands

on a sandstone plateau, cut into
deep ravines by the alzette river.
land reClamaTIOn The Old Town centers on the
Over the centuries, low-lying land has been
reclaimed from the sea. engineers built dikes Grand ducal Palace (1572), the
to enclose areas of shallow water, which were Cathedral, and the Town Hall.
then drained. From the 14th century, Porters carry trays luxembourg is a thriving
windmills were used to drain water of cheese at the
and pump it into canals. On the famous market industrial and banking center.
windswept lowlands, windpower was
in Alkmaar. CHeeSe

very effective, although it has now much of the cheese
been replaced by steam and electric produced in the
pumps. However, storms and high netherlands is made
tides are still a major threat to the from the milk of cows,
people of the netherlands. which graze on areas

of reclaimed land. The
country’s most famous
Windmills tap the cheeses are Gouda, and
energy of the wind edam, which has a red wax rind.
by means of sails
mounted on a
rotating shaft.

Find out more
europe

european union
Flowers and herbs
Ports and waterways

World war i

324

low countries

EU HEadqUartErs
In 1957, all three low countries were
Volcano Mountain Ancient Capital Large Small founding members of the European
monument city city/ city/ Economic Community (EEC). Brussels
town town

is now the administrative headquarters
BELgIUm of the European Union (EU), while
Area: 11,787 sq miles Luxembourg is the headquarters of
(30,528 sq km) the European Investment Bank and
Population: 11,324,000 the Court of Justice.

Capital: Brussels
Languages: Flemish,
French, german, dutch
Religions: roman Catholic, BELgIaN BEEr st Frisian Islands Schiermonnikoog
muslim Belgium is famous for its beer, which is
Currency: Euro Terschelling Ameland

LUxEmBoUrg produced in many local breweries and VlielandWe denzee Leeuwarden Groningen
Area: 998 sq miles exported worldwide. another important Wad
(2,586 sq km) export is fine Belgian chocolate; Belgium Texel
Population: 570,000 is the world’s second-largest exporter.
Capital: Luxembourg
Languages: Letzeburgish, Den Helder Assen

german, French NETHERLANDS
Religions: roman Catholic, Klazienaveen
Protestant, greek North Alkmaar IJsselmeer Almelo
orthodox, Jewish S e a Haarlem
Currency: Euro Lelystad Zwolle

Zaanstad
IJssel GERM
OAMSTERDAM A Enschede
N
NEtHErLaNds ScheldtTHE HAGUELeiden Apeldoorn Y
Area: 16,040 sq miles
(41,543 sq km) A ('S-GRAVENHAGE) Utrecht Amersfoort
Population: 16,948,000 FR
Capital: amsterdam, Lek N eder R ijn Arnhem
the Hague (’s-gravenhage) Dordrecht Wa l
Languages: dutch, Frisian SCALE BAR km Rotterdam a
Religions: roman Catholic, 0 50 100 MaasBergse Maas Nijmegen
Protestant, muslim Goeree
0 50 100 miles Over akkee Breda ’s-Hertogenbosch

Schouwen Zierikzee

MiNddoeorlbdu-Brgeveland RooTsehnodleanal Tilburg Helmond
Zuid-Beveland
Venlo
Currency: Euro Terneuzen Eindhoven
Ostend
(Oostende) Antwerp
Bruges
(Brugge)
(GGhneednenrtB)tARalUst SSREupMLeleSchLeeluenveHn aMssealtastricGhent k
Ijzer Roeselare t
Ieper
Leie
F Scheld
De
n d e r s Kerkrade
Kortrijk
l a

B E L G I U M(BRUSSEL/BRUXELLES)
Tournai Meuse Liège FagnB6es9ot4rmange
Mons Charleroi
Namur Hautes
Sambre
ne urthe
NN Famen es
Fagne Weiswampach
Bastogne
C E LUXEMBOURGW E
Recogne dSeemNonies unfchâSteûarue Diekirch
Ar Grevenmacher

S Arlon Alzette LUXEMBOURG
Virton M osselle

BrUssELs Esch-sur-Alzette

Brussels, the capital of Belgium, is an War CEmEtEry
international economic and financial the Flanders region of southwest Belgium
center. the city expanded rapidly in the is imprinted with memories of World War
19th century, and became the center of I. one of the costliest battles of the four-
Belgium’s growing steel, chemical, and year war was Passchendaele, in 1917, in which
textile industries. the grand Place an estimated 800,000 allied and german troops
(above) is the heart of the old town. were killed. Vast war cemeteries, such as tyne
Brussels is now a major financial center, Cot, near Ieper, also known as ypres (left), attract
with its own stock exchange. many visitors.

325

LUNGS aNd BREaTHING

We NeeD oXYGeN To lIve, and we get oxygen by breathing
air. When we breathe in, air is sucked through the nose or mouth,
down the windpipe, and into the lungs, two powerful organs
in the chest. The lungs absorb as much oxygen from the air
as possible. The oxygen travels in the blood from the lungs
to every part of the body. our bodies use oxygen to release
energy from sugars obtained from the food we eat. This also
releases harmful carbon dioxide, which is breathed out of the
body by the lungs. The whole process is called respiration. The
lungs, together with the airways, throat,
and nasal passages, form the respiratory Air flows in through the
nose and mouth, down
the throat, along the
hoW We MAke souNDs system. each lung is surrounded by two thin trachea (windpipe),
We use the air flowing in and coverings or membranes called the pleurae. and into the lungs.
out of our lungs to make sounds. The lungs themselves contain air tubes,
We speak, shout, laugh, and cry blood vessels, and millions of tiny air sacs Pharynx (throat)
by making air flow over two Larynx (voice
small leathery flaps called the box) at top
vocal cords. These are located called alveoli. If you spread these air of trachea
in the larynx (voice box), in the sacs out flat, they would cover the area
lower part of the throat. Muscles of a tennis court. Trachea
in the throat stretch the flaps (windpipe)
tighter to change from low
notes to high notes. divides into
two main
bronchi.
Lung
The rib cage is flexible, so
Breathing the lungs can expand and
Lungs fill with air shrink when we breathe.
as you breathe in.

Lungs empty
of air as you
breathe out.

Diaphragm
relaxes and rises.

Diaphragm
contracts
and flattens.

BreAThING ouT BreAThING IN Diaphragm is a dome-shaped Bronchi continue to
When you breathe out, the When you breathe in, the diaphragm sheet of muscle. branch and divide.
diaphragm and chest muscles contracts (becomes flatter) and pulls
relax. The lungs are spongy and down the base of the lungs. Muscles Bronchiole The alveoli are
elastic, so they spring back to between the ribs contract to swing grouped together
their smaller size after they have the ribs up and out. These actions like bunches of
been stretched. This blows air stretch and enlarge the lungs, so grapes. Tiny tubes
back out of the lungs. that air is sucked in. called bronchioles

luNGfIsh Alveolus bring fresh oxygen-
Most animals that live on Capillary containing air
land have lungs. Many water blood vessels to the alveoli.
animals, however, including
most fish, breathe using Oxygen-rich air Air with
feathery flaps called Alveolus carbon
gills. oxygen in the each alveolus is surrounded dioxide
water passes through by a network of very fine Air space
the thin gill coverings blood vessels called capillaries. inside alveolus
to the blood inside oxygen passes from the air
the fish’s body. The space inside the alveolus, Find out more
lungfish shown here through the lining, and into Brain and nerves
is an unusual animal the blood. Carbon dioxide heart and blood
because it has lungs and passes in the opposite way.
gills, so it can breathe in human body
both ways and can survive Muscles and movement

out of water for a long time. oxygen
skeletons

326

Machines

IncLIned PLane What do a saW and a computer have
simple machines reduce the
effort needed to move or lift an in common? Both are machines. one
object, but the object has to travel is simple and the other very complex,
a greater distance. the simplest but both are tools that do work for us.
machine is the ramp, or inclined Machines perform tasks that we would
plane. You need less force to push find difficult or even impossible to do.
an object with a downward load You cannot cut through wood with your
up an inclined plane than you bare hands, for example, but it is easy
need to lift it straight up. this with a saw. Likewise, a computer can do
is because the object moves a Force calculations rapidly that would take you an
greater distance along the plane. enormous amount of time. all machines need
the gentler the slope, the a source of energy. Mechanical machines,
farther you have to push, such as a corkscrew, use the energy of
but the easier it is. movement. a motor or a person’s muscles
Load drive the machine with a certain amount of
Effort Force force called the effort. the machine then
Steep slope— Gentle slope— applies this movement but produces a larger
large effort small effort force to move a load. For example, your fingers
operate a can opener, but the blade of the can
Load opener moves with much more force than that
produced by your fingers. Many hand-powered
screW machines help us perform tasks for which we do
not have enough strength. they use devices
a screw moves forward a known as simple machines. these include
shorter distance than it
turns. It therefore moves levers, gears, pulleys, and screws.
forward with a much
greater force than the
effort needed to turn it.
the screw bites into the
wood with great force
and is held strongly.

The screw makes PLoW
use of the principle the plow has
of the inclined plane. a cutting blade that
The thread of the screw bites into the soil
is like a slope wrapped and a V-shaped
around a cylinder. blade that turns
the soil over.

Archimedes’ screw (above) is an
ancient device for raising water. As it
turns, the screw shifts water along its
thread instead of moving itself forward.

PerPetual motion Wedge Effort
Many inventors have tried to the wedge is a form of inclined
build a machine that, once started, plane. Instead of moving a load Ax is a kind
would never stop. It would run along a slope, the wedge is of wedge
on its own without any source a slope that pushes a load Force
of energy. however, such a aside or upward as it moves
perpetual motion machine is forward. the wedge
impossible. this is because all pushes with greater
machines lose some energy as force than the effort
they work. Without a constant needed to move the
source of energy, a machine wedge. sharp blades Force
always slows down and stops.
are thin wedges that
In this machine, the motion of the balls make cutting
was supposed to keep the wheel turning. an easy task.

327

machines

Pulleys Small effort, but the AutomAtic mAchines
rope has to move Many machines do not need to
lifting a heavy load a large distance. be operated by people. These
is easy with a pulley Effort are automatic machines.
system. It contains a They contain mechanisms
set of wheels attached Pulley or computers to control
to a support. a rope themselves. These
goes around grooves Object moves a machines may simply
in the wheels. Pulling small distance. perform a set task
the rope raises the Force whenever it is required;
lower wheel and the Load automatic doors, for
load. a pulley system example, open as people
allows you to lift a arrive. Other machines are
heavy load with little able to check their own work
effort, but you must and change the way they
pull the rope a large operate to follow instructions.
distance to raise One example is an aircraft
the load by a autopilot, which guides the Traffic lights are machines that
small amount. plane through the skies. control traffic automatically.

Fulcrum

Gears lever
Gears are interlocking a long stick propped up on a small object
toothed wheels. They (a fulcrum) helps you move a heavy load.
The stick is a simple machine called a lever.
can increase force or Pushing down on the end farthest
speed depending from the fulcrum raises the
on the relative size other end with greater Effort A pair of scissors
of the wheels and consists of two levers
their number of force, helping you move
the load. Other kinds of hinged together.
teeth. a gearwheel levers can increase either Force
driven by a smaller the force applied to, or Load
wheel turns less quickly
than the smaller wheel the distance
but with greater force. moved by,
a wheel driven by a larger a load. Fulcrum
wheel turns faster but
with less force.

Force

Mechanical clocks and watches Fulcrum A wheelbarrow There are three types of levers.
contain gears that turn the hands Force is a second-class A crowbar is called a first-class
at different speeds. lever. The load lever. The fulcrum is between
Effort lies between the the load and the effort, which
fulcrum and is the force that you apply.
Wheel the effort.
Fulcrum
and axle Load Effort Force

several machines use the Effort
principle of the wheel and Load
axle. One example is
the winch, in which A fishing rod is
a handle (the wheel) a third-class lever.
turns a shaft (the The load moves
axle) that raises a greater distance than the effort,
a load. The handle but with less force. The effort pushes
moves a greater between the load and the fulcrum.
distance than the
load rises. The winch Load sTeerInG Wheel Find out more
therefore lifts the load The steering wheel on a car is an example Computers
with a greater force than of the wheel and axle. The shaft turns with
the effort needed to turn greater force than the effort needed to engines
the handle. turn the steering wheel. Industrial revolution

328 robots
Technology

MagnetisM

Origin Of magnetism the fOrce of magnetism is
iron contains millions of tiny
magnets called magnetic domains. invisible, yet you can see its power
normally, all of the domains point when a magnet drags a piece of
in different metal toward it. a material that
directions, attracts certain metals, such as
so their iron, is called a magnet. materials
magnetism cancels out. in that are attracted by a magnet are
a magnet, the domains point
the same way so that their
magnetism combines.
called magnetic. every magnet has two
poles—places at which magnetic objects
magnetic field cluster. earth itself is a huge magnet;
the area around a magnet in which
its magnetic force works is called
its magnetic field. for instance, its magnetic poles are close to the geographical
a paper clip is pulled toward north and south poles. One pole of a magnet is
the magnet (right) when it is
placed within the magnetic attracted to earth’s northern magnetic pole and is
field of the magnet. called the magnet’s north pole; the other is attracted to
the south and is called the magnet’s south pole. materials
All magnets attract that retain their magnetism all the time are called permanent
iron and steel magnets. an electric current flowing in a coil of wire produces
objects but not a magnet called an electromagnet
plastic or
wooden
ones. that can be switched on and
off. electromagnets are used in
electric motors, loudspeakers,
and many other devices.

Magnetic poles

SN SN

The north pole of one magnet
and the south pole of another
magnet attract each other.

NS SN

A magnetic pole, such as a
south pole, repels (pushes away)
another pole of the same kind.

lOdestOne The geographical North and South electrOmagnets
magnetite is an poles lie on Earth’s axis, which is the an electromagnet is a coil of
iron ore that line around which Earth spins. wire. an electric current within
often possesses the coil creates a magnetic
magnetism. it was The pattern of lines shows field. the field can be made stronger by winding
once commonly Earth’s magnetic field. The the wire around a piece of iron. turning off the
called lodestone, which field is strongest where the current switches off the magnetic field. some
means “guiding stone,” lines are closest together. cranes use an electromagnet instead of a hook.
because early navigators
used it as a compass. cOmpass
The magnetic north the needle inside a magnetic compass is
and south poles lie a
small distance away a thin, light magnet, balanced so that it
from geographical swings freely. the needle’s north pole
North and South. points toward earth’s magnetic north
geOmagnetism pole, which is very close to
earth produces a the geographical north. people
magnetic field that makes use magnetic compasses to
it seem as though it has a  navigate at sea and on land.
huge “bar” magnet inside it.
electric currents flowing within Find out more
earth’s liquid iron core cause earth
earth’s magnetism, which is
called geomagnetism. electricity
navigation

science

329

MAMMALS

the anImal GrouP called mammals includes the
heaviest, tallest, and fastest animals on land—the elephant,
the giraffe, and the cheetah. mice, whales, rhinoceroses,
bats, and humans are also mammals. like birds, A mammal’s
mammals are warm-blooded (endothermic), but three body is
features set them apart from all other creatures. covered in fur.
all mammals are covered in fur or hair, all feed
their young on milk, and all have a unique type of Young male
jaw. the jawbone helps us to identify the fossilized joey
bones of prehistoric mammals that lived on earth
millions of years ago. mammals are also members of the
group known as vertebrates because they all have
marsuPIal younG vertebrae (backbones). today, there are more than
marsupials are not completely 5,000 kinds of mammals, including carnivores (meat
developed when they are born.
after birth, the baby crawls
through its mother’s fur into eaters) such as tigers; herbivores (plant eaters)
a pocketlike pouch on the such as rabbits; and omnivores (meat and plant
abdomen, where it attaches eaters) such as bears. cattle, sheep, goats, and
itself to her teat, and stays
there until it is fully developed. most other farm animals are mammals, and
many pets are mammals, too, including cats,
dogs, and guinea pigs. mammals live nearly everywhere. they are
found on land, in the sea, and in the sky, from the coldest arctic
to the most searing heat of the desert.

A wallaby’s large tail is so strong that it
can act as a prop for the wallaby
to lean on.

Placental mammals
most mammals, including
monkeys, cats, and dogs, Pouched mammals
are called placental kangaroos, opossums,
mammals because the
young develop inside the wallabies, koalas, wombats,
mother’s womb, or uterus, and bandicoots are all known
and are fed by means of the
placenta. the placenta is a as pouched mammals or
specialized organ embedded in marsupials. these animals
the wall of the womb. It carries carry their young in their
nutrients and other essential pouches until the young are
materials from the mother’s developed and strong enough to
blood to the baby’s blood. these leave. once it has left the pouch, the
nutrients help the young grow joey (young wallaby) returns to the pouch if it
needs to suckle or if it is tired or threatened. marsupials
are found in australia and new Guinea, south america,
and north america. a few marsupials, such as the shrew
opossum of south america, do not have pouches.

and develop. after the young are
born, the placenta comes out of monotreme mammals
the uterus as afterbirth. Five kinds of mammals lay eggs. they are called
monotreme mammals, and include the platypus
and the four types of echidna (spiny ant-eater).
PrImates short beaked anteater all are found in australasia. after about 10 days,

monkeys, apes, and humans belong to a the young hatch out of the eggs, and then feed
group called primates. Primates are able on their mother’s milk.

to grasp with their hands. most primates the short-beaked echidna, lays a
have thumbs and big toes, with flat fingernails single egg in a temporary pouch
rather than claws. members of the primate on its abdomen. after the young
group range in size from the mouse lemur, echidna hatches, it stays in the
which weighs only 2 oz (60 g), to the pouch for 6 to 8 weeks. once
gorilla, which weighs up to 610 lb (275 kg). its spines start developing, it
is kept in a burrow.

330

MaMMals

MaMMal groups
There are about 27 main groups of mammals,
some of which are shown below. Rodents make
up half of all mammals; bats account for one-
quarter. There are only three kinds of elephants,
and the aardvark is in a group of its own.

Cats, dogs, and
other carnivores

Most puppies feed on their
mother’s milk for two or three
months. A mother shrew
Humans Elephants Camels, horses, and suckles her young for four
Aardvarks other hoofed mammals
weeks; a mother whale feeds her
youngster for six months or more.
mammal milk
Anteaters, Monkeys,
armadillos, apes, and
Bats and mammals are the only creatures that feed their young with milk.
and other flying foxes other primates
toothless When the female is about to give birth, she starts to produce
mammals milk in mammary glands on the chest or abdomen. When the
Sea cows Seals, sea lions,
and dugongs and walruses young are born, they suck the milk from the mother’s teats.

mother’s milk is an ideal food for the young—warm and
nourishing, and full of special substances that protect the young
from disease. as the babies grow larger and stronger, they take less
milk and begin to eat solid foods. This process is called weaning.
Whales,
dolphins, gestation
and porpoises

Rhinoceros The time between mating and

birth, when the young develop
in the mother’s womb, is called
Squirrels, the gestation or pregnancy
Hares, rabbits, Hedgehogs, moles, rats, mice, Tree The gestation usually lasts for 15 months; period. in general, large
and pikas and other insectivores and other shrews one young is born.
rodents
mammals have longer
Rabbit pregnancies and

Dirty fur harbors pests and fewer young than
also lets heat escape, so small mammals.
many mammals spend Gestation usually lasts for 30 days; as many
time cleaning or as eight young are born in a litter.
grooming their fur.

HaiR and fuR aRmadillo
fur or hair protects the mammal’s skin from injury and the Some mammals, such as
sun’s rays. it also keeps heat in and moisture out. The colors armadillos and pangolins,
and patterns of the fur provide camouflage. Water-dwelling have reptilelike scales instead
mammals such as beavers have special oily, waterproof fur. of fur. The scales, or scutes,
The porcupine’s spines are modified hairs and the rhinoceros’s of an armadillo are made of
horn is made from a hair-like fibrous substance. a type of horn and bone that
grows from the skin. Hairs
grow between the scutes and
also cover the animal’s soft-

skinned underbelly.

Body TempeRaTuRe Huskies are able to stay Find out more
warm in deep snow animals
mammals and birds are called warm-blooded because of their thick fur.
animals because they can maintain a high body animal senses
temperature even in cold conditions. mammals do, 331 elephants
however, need plenty of food to provide the energy
for warmth. The heat to warm a mammal is farm animals
produced by chemical reactions in the body, flight, animal
particularly in the muscles. Hibernation
prehistoric life

Manneldsoen la

1918 born in Mvezo, In february 1990, the 72-year-old nelson Mandela walked into freedom
transkei.
1942 Gained law degree; after spending more than 27 years in prison. He had spent his life opposing
practices in Johannesburg. the white-led South african government, which practiced the policy of
1952 becomes deputy apartheid, or separation of the races. Within four years Mandela led his
national president of party, the african national Congress (anC), to victory in the general
the anC.
1962 Imprisoned as a election and became the first-ever black
leader of the anC. president of a multiracial, democratic
1964 Sentenced to life South africa. by the time he retired in
imprisonment and sent to 1999, he was one of the most famous and
robben Island (until 1985).
1990 released from prison. deeply-loved political leaders in the world.
1993 Wins nobel Peace
Prize. afrICan natIonal ConGreSS
1994 elected first black
president of South africa. In 1912, the african national Congress was formed
1999 Steps down as to protect the interests of the black population of
president. South africa. It tried to achieve a multiracial,
2013 dies in Johannesburg. democratic country through peaceful means, but
the South african government thought it was
revolutionary, and banned it in 1961. from 1952,
Mandela was a senior member of the organization.

He became its leader in 1991.

robben ISland
nelson Mandela spent 18
of his 27 years in prison

on robben Island, a
high-security prison
off the coast of Cape
town. He broke rocks

in the quarry and
studied with other
anC prisoners. now the
prison is closed, and
people visit Mandela’s cell.

free nelSon Mandela trutH and reConCIlIatIon
People campaigned worldwide to In order to heal the wounds left by
free Mandela from prison. they apartheid, Mandela set up the
boycotted (refused to buy) South truth and reconciliation
african goods, such as fruit and Commission. a nobel Peace Prize
wine, and demonstrated against the winner, archbishop desmond tutu,
South african government. In 1988, ran the commission. It examined
a huge rock concert was held at the events of the apartheid era, and
london’s Wembley Stadium to tried to reconcile (bring together)
mark Mandela’s 70th birthday. former enemies.

WInnIe Mandela PreSIdent Find out more
In 1961, Mandela africa, history of
married Winnie the first multiracial elections in South africa were
Mdikizela (b. 1936). held in 1994. Mandela led the anC to a huge Human rights
She campaigned for victory and became president. He worked to obtain South africa
his release, but her peace, and unite all the peoples of his troubled
political activities were country. When famous people—including the
controversial. they Prince of Wales and the Spice Girls—came to see
divorced in 1996. him, he always wore one of his distinctive shirts.

332

1893 Born in shaoshan, MAO ZEDONG
hunan province.
1921 founding member of One man transfOrmed China from a backward peasant society into
Chinese Communist Party.
1928 establishes Chinese one of the most powerful nations in the world. that man was mao Zedong.
soviet (Communist) mao was born to a peasant family, and as a young man he traveled widely,
republic in Jianxi province. observing the conditions of the poor. he became interested in communism
1934-35 Leads the Long as a way to improve people’s lives and, in 1921, helped set up the Chinese
march. Communist Party. there followed a long period of struggle between the
1945-49 Leads Communists Communists, led by mao, and the nationalist Party (who
in fight to overthrow believed in strong national government), led by Chiang
nationalist government. Kai-shek. the struggle ended in a civil war. in October
1958 great Leap forward. 1949, the Communist Party was victorious and
1966-69 Cultural revolution. took power in China. mao proclaimed
1976 dies. China a people’s republic. Under
his leadership, the Communists
put everything under state control.
mao’s face became a familiar
sight. since his death in 1976,
many people have criticized
mao for causing the deaths
of millions during his rule.

LOng marCh Yenan

in October 1934, mao led his Communist Juichin
supporters from their stronghold, Juichin,
Kunming Route of
in Jianxi province to Yenan, in shensi the March
province, in northwest China. Jianxi The Long March

was under attack from Chiang Kai-shek.
more than 100,000 people marched for

more than a year, covering 6,000 miles
(9,700 km). Only 8,000 marchers
survived the ordeal.

CULtUraL
revOLUtiOn
after the failure
of the great Leap forward, mao lost
influence inside the Communist Party.
in 1966, he launched the Cultural
revolution, a campaign to regain
power and get rid of foreign influences.
for three years, China was in turmoil
as every aspect of society was criticized great LeaP fOrward
by the red guards, followers of mao. in 1958, mao launched a plan to improve the
they armed themselves with the Chinese economy. the great Leap forward, as it
Little Red Book, which contained was called, set up huge agricultural communes and
mao’s thoughts. encouraged the growth of small, labor-intensive
industries. however, the policy failed, leading to
millions of deaths through famine.
PersOnaLitY CULt
mao Zedong encouraged a cult of his personality to
unite the country. his round face, with the familiar
mole on the chin, adorned every public building in Find out more

China. he was praised as the father and leader of China
his nation, and huge rallies were held at which he Communism
addressed his followers.

333

Marsh and swaMp wildlife

the sAlt AnD FreshwAter hAbitAts of swamps ProbosCis monkey
and marshland are called wetlands. marsh and this large-nosed monkey
swamp wildlife includes crocodiles, frogs, birds, lives among the mangrove
fish, and countless plants. At different times
of the year, the water level of marshes and trees of river and coastal
swamps rises and falls. in the summer the swamps. the proboscis
monkey is a good swimmer.

Proboscis monkeys eat
leaves, flowers, and fruit.

land dries up, and in the winter it floods.
wetlands are generally unsuitable for large
mammals—except the African swamps where
hippopotamuses live. smaller mammals such
as muskrats live in north American swamps, and
the european marshes are home to many birds.
ConservAtion the main plant life consists of reeds, rushes, saw
Farming and industry threaten many grass, and cattail. large trees are found only in the
swamplands, but some animals, such tropical mangroves, where the trees form dense
as the marsh harriers shown here, thickets. willows and other waterside trees grow
are protected. they live in the Coto in the higher, drier ground around the marsh.
Doñana national Park in spain—one
of europe’s most important wetlands.

PeliCAn
most of these fish-eating birds build
their nests in remote marshland
areas. some species breed on the
ground, some in trees. others,
such as spot-billed and
Dalmatian pelicans, are very
rare because of destruction
of their nesting sites.

Front fins help the Cottonmouth
mudskipper walk on most snakes are
mud and grip roots. good swimmers
and climbers, and
muDskiPPer they can travel
this unusual fish has a through swamps with
store of water in its large ease in search of prey.
gill chambers, which allows the cottonmouth, also
it to live out of water for called the water moccasin, is a
long periods. From time to north American swamp dweller
time, it skitters over the mud swAmP rAbbit with a very poisonous bite.
to a pool to take in a new this large rabbit from north
supply of water. America can swim well and
dives to escape from predators. Swamp mud is usually so
swamp rabbits eat water plants, dense and waterlogged
grasses, and other vegetation. that, unlike normal soil,
it contains almost no
oxygen. The aerial roots
mArshlAnD of mangrove
trees stick
marshes are nursery areas for
up above
many insects whose larvae live the mud, to
in water, such as dragonflies absorb the
and mosquitoes. insect larvae oxygen they
and worms form the main diet need to grow.

of many fish and water birds.
Frogs, toads, and tadpoles are
also eaten by larger creatures.

mAngrove swAmPs Archer fish adjusts The drops of water hit the
mangroves are trees that grow in muddy its aim if it misses, insect like tiny bullets.
tropical swamps. some kinds of mangrove and fires again.
trees grow in freshwater; others tolerate Find out more
salty water and grow on the coast or in river ArCher Fish birds
estuaries. their roots and trunks trap mud, the archer fish Fish
and their seeds begin to grow while they
are still attached to the parent tree. when spits drops of Frogs and other amphibians
the seeds drop into the mud, they quickly water at insects on monkeys and apes
establish roots so they are not over-hanging twigs. seashore wildlife
washed away. the insects fall off the snakes
twigs, into the water, where
the fish gulps them down.

334

MatheMatics

proBaBility Sending a Spacecraft to a distant planet is like trying
tHeory
probability theory is to throw a stone at an invisible moving target. Space scientists
the analysis of chance. do not use trial and error; instead they use the science of
for instance, if you repeatedly mathematics to direct the spacecraft precisely to its target.
roll two dice, you can use probability Mathematics is the study of number, shape, and quantity. there are
theory to work out how often you can several different branches of mathematics, and they are valuable both
expect a certain number to come up. in science and in everyday life. for instance, arithmetic consists of
addition, subtraction, multiplication, and division of numbers;

it helps you figure out the change when you buy something.
geometry is the study of shape and angle; it is useful in
carpentry, architecture, and many other fields. algebra
is a kind of mathematical language in which problems
can be solved using symbols in place of varying or
unknown numbers. Branches of mathematics that
relate to practical problems are called applied
mathematics. However, some mathematicians study
pure mathematics—numerical problems which have
no known practical use.

infinity SyMMetry

pure mathematicians study the fundamental a symmetrical object is made up of alike parts. Many
ideas of numbers and shapes. one such idea symmetrical patterns and shapes occur in nature.
is the concept of infinity, which means “never- a starfish exhibits bilateral symmetry, since it
ending.” the pattern shown above is called looks the same when reflected in a line drawn
a fractal. it is produced by a computer along the length of one of its arms. this line
according to a strict formula (rule). you can is called an axis. the starfish also displays
enlarge any part of the pattern again and rotational symmetry, as it looks the same
again, but you will still get a pattern that is just when rotated around its central point.
as intricate. the pattern is infinitely complex.
The human face is asymmetrical.
If the left and right sides of this boy’s
face are reflected, the images that
result are different from
his actual face.

Euclid partS of a circle Circumference Radius aBacuS
the ancient greek a circle is a shape in the abacus, or counting
mathematician euclid Arc
(c. 330-275 bce) was the first which every point on its frame, is an ancient
to formulate theories on the circumference, or outside Sector calculating device which
nature of shapes and angles. Center comes from china. it consists
His book Elements outlined the margin, is the same of rows of beads that represent
principles of geometry, and it distance from the center. units of tens, hundreds, and
was a standard the diameter is the line thousands. the abacus is
textbook for that exactly bisects a circle, worked by moving the beads
centuries. passing through the center. along the rows. people in
euclid asian countries still use the
found many the distance from the abacus as a rapid tool for
practical uses center to the circumference
for geometry, adding, subtracting,
such as in is the radius. the slice of multiplying, and dividing.
optical circle between two radii is a
science. Find out more
sector, and the part of the computers
circumference that bounds Diameter numbers
Science, history of
a sector is an arc. Weights and measures

335

Maya Chichen Itza

Deep in the tropical forests of Mexico, the Mayan Palenque Tikal

people created one of the most amazing ancient civilizations, Copán
which reached its height between 250 and 900 ce. the Maya
built cities with huge stone temples. each city was the center PACIFIC
of a separate kingdom, with a king who was treated like a god. OCEAN
the Maya were great scholars who developed systems of
mathematics and astronomy. they even created their own writing Mayan civilization
system and used it to carve inscriptions about their history on stone the Maya came from the
plaques that they set up in their cities. Despite their sophistication, yucatan peninsula and the
the Maya had only the simplest technology. they used stone tools, highlands to the south, in
and did not know about the wheel. By the 1500s, the spanish had
conquered the region. what is now eastern
Mexico. they also built
cities in parts of modern
guatemala and honduras.

Outer shell of stone Temple contains
concealed earth base historic inscriptions.
and royal tomb.
flint carving Priests used the
craftworkers made their tools out of main staircase.
stones such as flint or obsidian (a
black, naturally-occurring glass). they
could work these materials to make a
sharp edge. the Maya became highly
skilled at this type of stoneworking,
and made intricate carvings in
strange shapes to show off their
skill. Many were made to
place in graves or as
offerings to the gods.

palenque People taking
part in
the temple of ceremonies
the inscriptions could stand
at palenque was a on the main
famous Mayan stepped
pyramid. Deep inside levels.
the base was a secret
chamber containing the glyphs
tomb of a local king, pacal, who died in Mayan writing was made up
about 684 ce. in the temple on top of the of a series of signs that
pyramid were stone tablets carved with glyphs archaeologists call glyphs.
that recorded the history of the local kings Many of the glyphs were
up to pacal’s reign. its ruins still exist today. simplified pictures of the objects
they stood for. some represented
Stone ring Players used their sounds, which were used to build Pot shaped
acted as “goal.” elbows to hit the ball. up words. others were symbols like a jaguar
that stood for different numbers.
the Maya used glyphs to record BlooD sacrifice
their calendar, and to write some Mayan communities believed
inscriptions about their history. that their gods would be pleased if
Glyph describing a Mayan
noblewoman called Lady Xoc people were killed in their honor.
they also saw sacrificial blood as
Ball gaMe
Many cities had a ball court where people played food for the gods. in some places a
a game with a rubber ball. players wore padded pot shaped like a jaguar, a beast
clothing, and were only allowed to touch the ball sacred to the Maya, was used to
with their hips, arms, or elbows. the aim was to get collect the blood.
the ball through a small stone ring at the side of the
court. players who lost were sometimes put to death. Find out more
Bronze age
central america

Wheels

336

Medicine

Two HundRed and fifTy yeaRs ago, people lived on
average for just 40 years. Today, in some industrialized parts of
the world, the average lifespan has increased to more than
80 years. Better food and hygiene have helped, but one of
the main reasons for this change is the advances made in
medicine. Medicine is the branch of science concerned
with the prevention, diagnosis (identification), and
treatment of disease and damage to the human body.
Medical scientists are constantly searching for new ways
of treating diseases. Treatments include drugs, radiation
therapy, and surgery. Preventive measures, such as
vaccinations against infections, are becoming an
increasingly important part of modern medicine.
diagnosis
a doctor’s first step with a sick patient is to diagnose
the illness. This can be done in various ways—by asking suRgeRy
the patient about his or her symptoms (physical Medical treatments may include drugs
feelings), by making a physical examination of the sick or surgery. surgery is the branch of
person, and by carrying out medical tests if necessary. medicine that involves operating,
or cutting into the body, to treat
the cause of an illness. Today
surgery is so advanced that
surgeons can sometimes repair
Branches of medicine or replace organs such as the
Medicine is a huge subject, and nobody can hope kidneys and the heart.
to know it all. Thus doctors, nurses, and other
medical workers often become expert in a single
area of medicine, a process that can take years
and years of study.

Neurology Ophthalmology Orthopedics is the Psychiatry is the RecoveRy
is concerned is the treatment care of the spine, study of mental Recovery from an illness or an
with disorders of disorders of bones, joints, and health problems. operation may take only a few
of the brain the eyes. muscles. hours or as long as several weeks.
and nerves. Much depends on the severity of
the illness and the impact the

treatment has on the body.

Cutting into the body Dermatology is Pediatrics is the Medical
to cure illness is concerned with the skin medical care of
called surgery. and skin diseases. children. TecHnology

Rue is prescribed for some Catmint is a cold cure Modern medicine makes
digestive disorders. that was first used by use of a wide range of
prehistoric people. technology. latest
developments include body
HolisTic Medicine Doctors use MRI scanners to scanners that use a strong
The word holistic means check patients for tumors or magnetic field or ultrasound
damage to the brain. (very high-frequency sound
“of the whole”. The principle waves) to produce an image
of holistic medicine is to treat of the interior of the human
the whole person—body and mind— body. such equipment has
Mint is used rather than just the affected part. Holistic revolutionized medicine.
for settling an
upset stomach. therapies (treatments) include acupuncture Find out more
(stimulating the nerves by inserting needles disease
into the skin) and aromatherapy (treatment drugs
using oils containing fragrant plant extracts).
Health and fitness
Human body

Medicine, history of
Muscles and movement

Technology

337

TrepanninG M HISTORY OF
Ten thousand years ago, healers
tried to cure a sick person by cutting EDICINE
a hole in his or her skull. Healers
believed that the hole in the head sinCe THe earliesT Times, people have looked for ways of curing
released evil spirits that caused pain.
This was known as trepanning. their illnesses. early people believed that disease was a punishment from
the gods. They also believed that priests and magicians could heal them.
in ancient Greece, people visited temples when they were sick and
sacrificed animals to asclepius, the Greek god of healing. They also drank
and bathed in medicinal waters and followed strict diets in the hope of
being cured. During the 5th century bce, the Greek doctor Hippocrates
declared that it was nature, not magic, that caused and cured disease.
Hippocrates was famed as “the father of medicine,” and he and his
followers wrote many medical books. The spirit of enquiry, which was part
of the renaissance (a cultural movement beginning in 14th-century
europe), encouraged experiments that put european medicine on a firm

scientific basis. many people began to question the traditional ideas
about medicine. scientists such as vesalius (1514-1564) began to
study the bodies of dead people to learn more about diseases and
how to treat it. since then, there have been many more discoveries
in medicine, and the battle against disease continues.

Humors
The Greek physician Galen (c. 130-200 ce)
introduced the idea that the body contained four
fluids called humors—blood, phlegm, yellow
bile, and black bile. He believed that a person’s
mood depended on which of these four fluids
ruled the body, and that if the fluids were not
balanced, illness
would result. Herbalism

William Harvey For thousands of years, people have used herbs and plants in
in 1628, an english doctor healing. Herbalists wrote lists of herbs and their uses. monks were
named William Harvey
(1578-1657) discovered also famed for their knowledge of herbs. The first pharmacists,
that blood constantly called apothecaries, used herbs to make potions, or medicines. in
circulates around the
body. He described how europe during the renaissance, however, many herbalists were
blood is pumped by the accused of being witches. many people are now turning to
herbs as a natural way of treating illnesses.

heart into the arteries Harvey drew detailed diagrams to
and returns to the heart through explain his theory of circulation.

the veins. He showed that valves
in the veins stop the blood from
flowing backward. at first, Harvey
was scorned for contradicting old
ideas, but later he became physician
to Charles i, King of england.

338

Carbolic acid MEDICINE, HISTORY OF
was sprayed
continuously AntiSePtiCS
over operating until the late 19th century, surgeons did not wash
area from a their hands or their medical instruments before
special pump. operating on a patient. Many patients died from
deadly infections following an operation. Joseph
lister (1827-1912), an english surgeon, guessed
that infection with bacteria might be the cause of
these deaths. in 1865, lister developed an
antiseptic spray called carbolic acid. this
spray could destroy bacteria in the operating
room, so there was a dramatic drop in the
number of deaths following operations.

Leeches are parasites that
attach themselves to a host.
They secrete a substance
that stops blood clotting
while they feed on it.
Blood-letting
doctors once
believed that too
much blood in the
body was the cause of
disease. they removed the
excess blood by blood-letting.
doctors either cut open a vein to let the
blood out, or they applied bloodsucking
AlexAndeR FleMing creatures called leeches to the body. the
leech attached itself to the patient with its
Bacteria cause many of the illnesses that affect sucker, made a wound, then sucked out blood.
humans, so for years scientists tried to find a the exact spot for blood-letting depended on
what was wrong with the patient.
substance that would kill bacteria but would
not harm human tissue. the Scottish history of medicine
bacteriologist Alexander Fleming c. 8000 bce early healers
practice trepanning.
(1881-1955) was the first person to identify 400s bce Hippocrates, a greek,
an antibacterial substance. Fleming begins scientific medicine.
1543 Vesalius publishes first
carried out his research in a laboratory at scientific study of human body.
Saint Mary’s Hospital, london, england. 1615 Santorio, an italian doctor,
in 1928, Fleming noticed that a mold that designs mouth thermometer.
1683 Anton van leeuwenhoek,
had accidentally developed on a dish of a dutch scientist, discovers
bacteria culture caused the bacteria to bacteria.
1796 edward Jenner gives first
die. in 1941, the researchers Howard smallpox vaccination.
Florey and ernst Chain purified the 1816 Rene laennec, a French
doctor, invents stethoscope.
mold, Penicillium, to produce penicillin, 1842 American surgeon,
the world’s first antibiotic. Penicillin is Horace long, operates using
widely used in the treatment of many general anesthetic.
diseases, including meningitis and 1895 Wilhelm Roentgen, a
german physicist, discovers
pneumonia. Fleming shared the 1945 nobel x-rays, which enable doctors to
Prize for Medicine with Florey and Chain. see inside the human body.
1900s Polish-born Marie Curie
medical Pioneers SigMund FReud and her husband, Pierre Curie
through the centuries the Austrian doctor Sigmund Freud of France, discover the chemical
many people have shaped (1856-1939; below) was interested in element radium to treat cancer.
modern medicine. the finding out how the mind works. He 1900s Scottish bacteriologist,
Flemish doctor Vesalius treated patients with mental disorders by Alexander Fleming, discovers
produced accurate listening to them talk about their dreams penicillin.
drawings of the human and thoughts. this treatment
body; dutchman Anton was called psychoanalysis. in
van leeuwenhoek
(1632-1723) first 1900, Freud published The
discovered microbes, Interpretation of Dreams,
which explained
his method.

now called bacteria;
and the english doctor louiS PASteuR
edward Jenner Frenchman louis Pasteur Find out more
(1749-1823) discovered (1822-1895; above) showed drugs
vaccinations—a way that bacteria caused disease.
of preventing certain He invented pasteurization— egypt, ancient
diseases by injection. the heating of milk and beer greece, ancient
to destroy harmful bacteria.
Medicine

339

MEDIEVAL EUROPE

Fairs Lords and Ladies feasting in castle banquet halls, peasants
Great fairs were held every year in towns, such as
Winchester, england, which were on important working on the land, knights in armor—all these are associated
trade routes. Merchants traveled from all over with a time in european history known as the medieval period
europe to sell their goods at these fairs. or the Middle ages. This was a time of great change in Western
europe between the 5th and 15th centuries. during the 5th century,
Everyone Windmill to the roman empire fell, to be replaced by smaller kingdoms set up
gave part of grind grain by invading Germanic tribes in Western europe. Trade collapsed,
their crops and people had to make their living from the land. Gradually,
to the village powerful landowners, or lords, emerged and the feudal system
church. developed. The early medieval period of europe is sometimes called
the dark ages because the learning of ancient Greece and rome
almost disappeared. But the Christian church gave leadership to the
people. Trade gradually improved. By about the 13th century, the
Middle ages had reached their height. Feudalism governed society,
and monasteries (where monks lived) were the centers of learning.
The medieval times came to an end in the 15th century, when the
renaissance swept through europe.

Plowman
working on
the land
around the
village.

Farmers The manor
herding house was
sheep the largest
through house in the
the village. village. It
was built
of stone.

Most Stables
buildings “Mystery”
in the religious plays
village had were popular
thatched throughout
roofs. medieval

Europe.

Chopped wood served Traveling musicians The village fair was ViLLaGe LiFe
for repairs to the house entertained people at held twice a year.
the fair. Sometimes there Two or three huge open fields usually
and to make fire. were dancing bears. surrounded a medieval village. The lord of
the manor owned the land, but the peasants
farmed it, in scattered narrow strips, and kept
most of what they grew. They worked hard all
year round and paid taxes to the lord and the

church in the form of work and goods.

340

mEDIEVAL EUROPE

Shoemakers medieval europe
400 ce Roman empire
Town scene begins to decline.
450 German tribes—
Trade increased in the angles, Jutes, and
later medieval period, saxons—settle in Britain.
making merchants wealthy 480s Franks set up
and powerful. Towns became kingdom in Gaul
important trading centers with (now France).
a new class of craftspeople. The 800 charlemagne, king
craftspeople created organizations of the Franks, unites
called guilds to control the prices western europe.
and quality of their goods. 900-1000s europe is
divided into feudal
People bought estates; there is
fabric to make widespread poverty and
their own clothing. disease in the region.
1066 normans conquer
The poultry england.
trader sold 1000s-1200s High middle
geese. ages: trade improves,
FeUdaLism population grows, towns
Kings gave their develop, and learning
vassals—powerful nobles—tracts flourishes.
of land called fiefs. in return for this land, c. 1100 First universities
the vassals fought for the king when required. are founded.
The vassals divided their land into manors 1215 magna carta:
(estates), which they gave to lesser nobles and english barons win
knights. in return, the knights and lesser nobles power and rights
worked for the lord of the manor, and had to from King John.
fight for him when called on. 1300-1500 Late middle
ages.
14th-century manuscript (right) c. 1320 Renaissance,
shows feudal structure, with a rebirth of arts and
the king at the top. learning, begins in italy.
1337 Hundred Years’
war begins between
england and France.
1348 Black death, a
killing plague, reaches
europe. eventually, it
wipes out one-third of
the population of europe.
1378-1417 Great schism:
catholic europe is
divided in support of two
different popes, Urban Vi
and clement Vii.
1454 Johannes
Gutenberg, a German,
develops movable type.
Printing begins
in europe.

Hunting (above) was a women Find out more
popular sport for upper- Peasant women worked very hard all their lives. Black death
class medieval women. They brought up their children, spun wool and europe, history of
A French medieval wove clothing, and helped with all the farmwork. Knights and heraldry
woman, Christine de Upper-class women also led busy lives. They often Renaissance
Pisan (left), earned her ran the family estates while their husbands were Roman empire
living as a writer. away traveling around their lands, fighting
against neighboring lords, or on a crusade to
the Holy Land. women also nursed the sick and
provided education for children in their care.

341

Metals

IMAgInE A WoRld WIThouT METAlS. There would be no cars or airplanes,
and skyscrapers would fall down without the metal frames that support them.
Metals have countless uses because they possess a unique combination
of qualities. They are very strong and easy to shape, so they can be used to
make all kinds of objects—from ships to bottle tops. Almost all metals conduct
electricity. Some are ideal for wires and electrical equipment. Metals also
Gold carry heat, so they make good cooking pots. These qualities can be
watch improved by mixing two or more metals to make alloys. Most metallic
Mercury thermometer Copper objects are made of alloys rather than pure metals. There are more
wire

than 80 kinds of pure metals, though some are very rare. Aluminum
and iron are the most common metals. A few metals, such as gold,
occur in the ground as pure metals; the rest are found as ores in
rock. Metals can also be obtained by recycling old cars and cans.
Silver- This reduces waste and costs less than processing metal ores.
plated
frame

PuRE METAlS Airplane fuselage made
of aluminum alloys
The rarity and luster
of gold and silver have been prized

for centuries. other pure metals
have special uses. Electrical wires are

made of copper, which conducts
electricity well. Mercury, a liquid
metal, is used in thermometers.

Aluminum A lump of Alumina Molten AlloyS
The most common poured Carbon aluminum
bauxite in here electrode ElECTRolySIS Most metal objects are
Passing an electric made of steel or other
metal in Earth’s current through alloys. This is because alloys
crust is aluminum. alumina separates are often stronger or easier
The metal comes it into aluminum to process than pure metals.
from an ore called and oxygen. This Copper and tin are weak
bauxite, which process is called and pliable, but when
contains alumina, electrolysis. mixed together they make
a compound of a strong alloy called bronze.
aluminum and Brass is a tough alloy of
oxygen. Aluminum is light, conducts copper and zinc that resists
electricity and heat, and resists corrosion. corrosion. Alloys of
These qualities mean that the metal and aluminum are light and
its alloys can be used in many things, strong and are used
including aircraft and bicycles, window Thin, flexible aluminum foil is to make aircraft.
frames, paints, cookware, and electricity useful for cooking and storing
supply cables. food because it is nonreactive WEldIng
and can stand high temperatures. Metal parts can be joined by
welding. Welders apply heat
METAl fATIguE METAlWoRkIng from a gas flame or an electric
Metals sometimes fail even spark to the edges of two pieces
though they may be very There are many ways of of metal. The heat causes the
tough and strong. Corrosion shaping metal. Casting edges to melt so that they can
weakens some metals, as in be joined together.
the case of rusty steel. is one method of
Repeated bending can cause making objects such as Find out more
metal parts to break—an Bronze age
effect called metal fatigue. metal statues. hot,
Keys may break after molten metal is Iron age
considerable use. Iron and steel
poured into a mold Rocks and minerals
where it sets and
hardens into the Science

required shape. Metal
can also be pressed,
hammered, or cut
into shape.
342

Mexico is part of the continent of Mexico
north america and lies between
the United States to its north and the wealth Of MexiCO has traditionally come from the land.

Central america Precious metals lie buried in the mountains and rich crops grow in
to its south. the valleys. Oil flows from wells on the coast. the Mexican people began
to exploit these advantages centuries ago. farming supported most of the
people, and from the country’s mines came silver to make beautiful jewelry.
the mineral wealth of the country attracted invading europeans early in the
16th century, and Spain ruled Mexico for the next three centuries. a revolt
against Spanish rule gave the Mexican people independence in 1821. the
discovery of oil early in the 20th century brought new wealth to Mexico.
the government invested this wealth in new factories, and in social services
to relieve hunger and improve health and education. in 1994, the north
american free trade agreement (nafta) reduced trade barriers between
Mexico, Canada, and the United States, promising long-term economic

benefits. however, the border between Mexico and the US has been
strengthened as a result of
US concern over the
many illegal
crossings made
each year.

José Guadalupe
Posada (1852–1913)
drew humorous
illustrations, many of
which supported the
POlitiCS and revOlUtiOn Mexican Revolution.
Mexico was a Spanish colony from 1521 to 1821,
when it became an independent republic. after a long
period of political unrest, there was a revolution in 1910,
in which half a million people died. from 1929, the
institutional revolutionary Party (irP) governed Mexico.
however, in 2000 it lost the presidential election for the MexiCO City
first time. Mexico is now a functioning democracy.
around 21 million people live in and around Mexico City, the
capital of Mexico, making it one of the most populous cities in
Cinnamon Sweet potatoes the world. the city lies 1 mile (1.6 km) above sea level in a
sticks Mangoes natural basin surrounded by mountains. these mountains trap
the pollution from the city’s industries. as a result, Mexico City
is one of the world’s most unhealthy cities, with
an inadequate water supply, a lack of housing,
and the constant threat of earthquakes adding
to its many problems.
Chilies

Corn

Beans Mexican artisans are skilled
at making fine jewelry from
the precious metals found
in their country.

Bananas Mineral wealth
Copper, silver, zinc, mercury,
Farm produce and other valuable metals are
Only one-seventh of the population among the many minerals found
of Mexico works on the land, growing staple or in Mexico. Oil is the country’s most
food crops. increasingly, however, farmers are important resource. in 1974, vast
growing coffee, cotton, sugar, and tomatoes for new reserves were discovered in
export. these cash crops take vital land away from the south of the country.
the crops that the Mexican people themselves need
for food. Most of the farmers are members of Find out more
cooperatives, pooling their limited resources Conquistadors
to help one another. north america

volcanoes

343

Mexico

Volcano Mountain Ancient Capital Large Small
monument city city/ city/
town town

statistics Sierra Madre
area: 758,450 sq miles The main mountain system
(1,964,375 sq km) of Mexico, the Sierra Madre, runs
Population: 121,737,000 1,500 miles (2,400 km) southeast
capital: Mexico City from the border with the United
Languages: Spanish, States. There are three ranges—in
Nahuatl, Maya, Zapotec, the east, south, and west—and they
Mixtec, Otomi, Totonac, enclose Mexico’s central plateau.
Tzotzil, Tzeltal Mexico’s third-highest mountain,
Religions: roman Catholic, Volcán iztaccihuatl (right), is in the
Protestant Sierra Madre del Sur, the southern range.
currency: Mexican peso The mountain has three separate summits,
Main occupations: and its name means “White Woman” in the aztec The tallest
Subsistence farming, language, because the peaks resemble peak of Volcán
manufacturing, oil a woman wearing a hood. Iztaccihuatl rises to
production POPUlaTiON 17,159 ft (5,230 m).
Main exports: Oil, cotton, Most of northern Mexico is sparsely populated GUaNaJUaTO
machinery, coffee because of the hot, dry climate and lack of good Spanish prospectors searching for gold
Main imports: Machinery, farmland. as people have migrated from the founded Guanajuato (below) in 1554.
vehicles, chemicals countryside in search of work, the cities have grown The town is the capital of Guanajuato
dramatically; almost 80 percent of Mexicans now state in the mountains of Central Mexico
live in urban areas. Mexico City is home to almost and rises more than 6,726 ft (2,050 m)
one-quarter of the population and is one of the above sea level. it is built in a ravine and
world’s largest cities. rapid, unplanned growth has has steep, winding streets.
led to poor sanitation and water supplies.

N riO GraNde
The Rio Grande
flows from Colorado
in the United States
Tijuana Mexicali W E and forms much
of Mexico’s
Isla Cedros L o w erGulf UNitED statEs OF S northern border.
It crosses
ciudad Juárez R aMERica a vast arid region
io Grande on its way to the
Gulf of Mexico.
S ierra
Isla Ángel
de la Guarda

Hermosillo
of

C Yaqui chos

baJa C chihuahua Con Rio Grande
CalifOrNia a
Baja California tEMaLa
al Ciudad
l Obregón

i Madre

f
i

or
f

is also called n Monclova Nuevo Laredo
Lower California. o

i

a
r

The peninsula is n Los Mochis Gómez scaLE BaR
Guamúchil Palacio 0 200 400
Isla i Reynosa
in Mexico, and is Magdalena Culiacán O ccidentalME 0 200
a Torreón Monterrey Matamoros km
not part of the US 400 miles
X i c OSaltillo
state with which Tropic of Cancer Tropic of Cancer
it shares a name.
Durango S i erra Gulf of
Mazatlán
San Lucas Cape Ciudad Victoria
M e x i c oPotosí

Aguascalientes
san Luis

IslMasaTríra Tepic M adre Tampico Yucatan Channel

s es Guadalajara León

P A Poza
Rica
C Puerto Vallarta Querétaro O riental Bay of Campeche Mérida Cancún

I Morelia Campeche Yucatan Isla
F Cozumel
MEXicO citY
Volcán Iztaccihuatl 5230m Xalapa

wbopoarbrTnnlModehcdbe,ei eenguyXneMcteihoitCxnemetpgxiamgeeiNbcirterarrtlsiinfwcg.oaThpendbateheltvroyesheipiycgerClosnaelSlrsesoehIi,fnrtlase.icvkkdTeeCieolfltdeahbdaeryaiscmttsrO,oipwsteitdMhCsekxiirctEaancBaaAlpsaSus ilecNrorPaopoMc5a4t5éap2emdtl Puebla Veracruz Carmen Peninsula

r e Minatitlán Coatzacoalcos BELiZE
del Sur Villahermosa

Oaxaca Volcán El Chichónal
1060m

Tuxtla Comitán

fabrics are mass-produced in large factories. Gulf of GUa
Tehuantepec

Tapachula

344

Observer looks Microscopes
through eyepiece.
Objective lenses of WitHin all obJects there is a hidden world that is much
different power can be too tiny for us to see. With the invention of the microscope
swung into position in the 16th century, scientists were able to peer into this
when needed. world and unravel some of the great mysteries of science.

they discovered that animals and plants are made of
millions of tiny cells, and later were able to identify the
minute organisms called bacteria that cause diseases.
The objective early microscopes consisted of a single magnifying lens;
lens produces an
image which the
eyepiece magnifies today’s microscopes have several lenses and can be used
(makes larger). to see very tiny objects. electron microscopes are even

more powerful. instead of light, they use a beam of
electrons—tiny particles that are normally part of
The object being atoms—to magnify objects many millions of times.
studied rests on
a glass slide. scientists use electron microscopes
Condenser lenses to study the smallest of living
concentrate a cells and to delve into the
beam of light structure of materials such
onto the object. as plastics and metals.

A strong beam
of light strikes a
mirror under the
microscope.
The beam shines
onto the object Optical microscopes can reveal
living cells such as these cells
from below. that come from a human cheek.

They are magnified more than
200 times.

optical microscope
the optical, or light, microscope has two
main lenses: the objective and the eyepiece.
High-quality microscopes contain several
additional lenses that help to give a clear, bright
image. Different objectives can be fitted that give
a range of magnification from about 10 times
to 1,500 times normal size.
electron microscopes
objects must be cut into thin
slices in order to see them with
InventIng the mIcroscope a microscope. However, a
scanning electron microscope
can magnify a whole object
such as this ant (right), which
is about 15 times
normal size.

although the romans used magnifying With a
lenses about 2,000 years ago, the first scanning
true microscope appeared around electron
1590, built by Dutch lensmakers microscope the
Hans and Zacharias Janssen. in 1663, image appears
english scientist robert Hooke studied on a monitor.
insects and plants with a microscope.
He found that cork was made up of tiny imaging atoms Find out more
cells, a discovery of great scientific special electron microscopes can show individual atoms and molecules
importance. microscopes aroused great atoms, which are so small that a line of 0.5 million
interest in microscopic life, as this old atoms would only span the width of a human hair. biology
etching shows. this piece of silicon (above) is magnified microscopic life
45 million times, revealing its atoms.

345

MICROSCOPIC LIFE

All ARoUnD US there are living things that we
cannot see because they are too small. They
Dust mite float in the air, they swim in puddles and

oceans, and they coat rocks, soil, plants,
and animals. Microscopic life includes
bacteria and viruses; single-celled
organisms called protoctists; and
single-celled plants called algae.
It also includes the microscopic stages in
the lives of larger plants and animals, such
as the tiny pollen grains of flowers and
the spores of mushrooms. From bacteria
to algae, all are so small that we can see
them only through a microscope. Viruses,
which are the smallest and simplest of all
living things, must be magnified one
million times before we can see them.
Microscopic life has a crucial role to play.
Plankton consists of millions of algae and
protozoa, and is an important food for water
creatures. Bacteria in soil help to recycle nutrients.
DUST MITe Some microscopic life, such as bacteria, can cause disease.

This microscopic animal can
be found in anyone’s home. It lives among dust, Amoeba divides in half, forming
fluff, cat fur, and bits of dirt. Dust mites eat the AMoeBA two daughter cells.

dead skin you shed every day. The amoeba is
a single-celled
organism. It lives in
ponds and puddles.
We need to magnify
an amoeba at
least one thousand times
before we can see it.
The amoeba moves by
stretching out a part of its body
known as a pseudopod, or “false
foot.” The rest of the body then
flows into the pseudopod.
Amoebas feed by engulfing prey
such as bacteria with their
pseudopods; then the whole
DIAToM AlgAe body flows over the prey. Nucleus—
Microscopic plants called diatoms The slimy scum that you see on control center
live in lakes, rivers, and oceans. There the surface of a stagnant pond is Food is stored in a Pseudopod
are thousands of different kinds of blue-green algae. These algae are small bag called (false foot) of amoeba
diatoms, providing food for many not true plants. They are more the food vacuole. Cell membrane,
insects and water creatures. Diatoms closely related to bacteria. Blue- the skin around
live and grow by using sunlight and green algae were among the first the cell

the nutrients in the water. Around forms of life to appear on earth HoW An AMoeBA RePRoDUceS
their bodies are strong shell-like more than 2,000 million years ago. To reproduce, the amoeba divides into two. This is
walls made of silica—the same called fission. First the nucleus splits in two, then the
material found in sand grains. Passionflower rest of the body divides in half to form two separate
Pollen pollen grain amoebas. These are called daughter cells.

Microscopic grains of Hollyhock Find out more
pollen grow on the male Disease
part of a plant, called the
stamen. each kind of plant Human body
has a different type of Microscopes
pollen grain with its own ocean wildlife
pattern and shape.
pollen grain

346

middle east

the Middle east consists of 15 Less than 100 years ago, many of the inhabitants of the Middle east
independent countries. they sit
at the crossroads of three great were Bedouins—desert-dwelling nomads who lived in tents and led their
continents—to the northwest animals in search of food. the rest of the population lived in small towns
lies europe, to the southwest is and villages and made a living as farmers or craftsworkers. almost everyone
africa, to the north and east are was poor and uneducated. today, the lives of their children and
the caucasus and central asian grandchildren have been transformed by the discovery of oil. Many
republics, all part of asia. people have grown rich from the new industries and services related to
oil production and refining. In some countries, notably Kuwait and Bahrain,
WaterWays there is free education and medical care for everyone. oil transformed the
international importance of the Middle east as well. the region had little
rising in the mountains influence in world affairs. now it controls one-quarter of the world’s oil
of turkey, the tigris and production, and decisions made in the Middle east affect the economies
euphrates rivers irrigate of europe, the americas, and asia. But despite this massive change,
the almost rainless land traditional customs have not been
of the Middle east as they completely abandoned, and the
flow in parallel to the religion of Islam continues to
persian gulf. the fertility of dominate daily life throughout
the euphrates-tigris delta, the Middle east, as it has done
known as Mesopotamia in for more than 1,300 years.
ancient times, gave rise to
the world’s first cities. ModernIzatIon
the discovery of oil brought great wealth and

rapid industrial and social change to the
Middle east. But governments in the region
recognize that the oil will eventually run out, so
they have spent some of the money they earned
from selling oil in encouraging and modernizing
local industry and business. Many Middle eastern
countries have also invested in property and businesses

in other nations throughout the world.

The shopping malls of the Middle East are well known
for their opulence and famous luxury stores.

The areas
bordering the
Euphrates and
Tigris rivers are
swamps and Landscape and cLIMate
marshlands. Here,
small boats Most of the Middle east consists of hot,
replace the camel dry, rocky deserts. a crescent of fertile land
as the most stretches west from the tigris and euphrates
common means
of transportation. rivers through northern Iraq and syria and
then south into Lebanon and Israel. turkey
and Iran are mountainous, as are the
southern parts of the arabian peninsula.
In the southeast of saudi arabia lies the
Camels are well rub’ al Khali, a vast, uninhabited sandy
adapted to the harsh desert known as the empty Quarter.

conditions of the
Middle East, and are
still a popular form
of transportation.

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Middle east

suEz CANAl
More than 100 miles (160 km) in length, the suez Canal links the
Mediterranean sea and the red sea. The canal took ten years to
build, and, when completed in 1869, it cut more than 7,000 miles
(11,000 km) from the distance that sailing ships traveled to reach the
Far East. Today, more than 1,400 ships pass through the canal each
month. The suez Canal is an important trade route and has often
been at the center of conflict in the Middle East. The waterway has
been closed by war and political disagreements several times, most
recently by the Arab-israeli six Day war of 1967. in 2015, a second
lane was completed, which would allow more ships to pass through.

The Suez Canal is not wide DubAi
enough for ships traveling in The city-state of Dubai on the
opposite directions to pass Persian Gulf has a modern center,
each other. Vessels must travel but on the outskirts it merges into
in convoy (above), passing only the surrounding desert. rainfall
at bypasses, where stretches on the Arabian Peninsula where
of the canal has been doubled. Dubai stands averages less than 4 in
Splendid architecture, financed by (100 mm) a year, and in most places
revenue from oil, can be found in the only natural water comes from
Abu Dhabi, such as the underground springs. Desalination
Aldar headquarters plants turn salt water from the
building (right).
Persian Gulf into a supply
of drinking water for the city.

Abu DhAbi Dubai, part of the federation of the
The rulers of many Middle East states invested income from United Arab Emirates, is generally flat.
sales of oil to improve the living conditions of their people and
to develop the economies of their nations. in the 1960s, the uNiTED ArAb EMirATEs
city of Abu Dhabi was just a fishing village on the Persian Gulf.
Today, it is the capital city of the Abu Dhabi sheikdom in the like many Middle East nations,
united Arab Emirates, complete with an international airport the united Arab Emirates has no
and high-rise downtown area. Abu Dhabi’s revenues from oil democratic government. instead,
royalties give it one of the world’s highest per capita incomes. the country is ruled by a group
of wealthy emirs (kings) who have
absolute power over their people.
Each emir controls his individual
emirate, or kingdom, but they
meet in the Federal supreme
Council of rulers to make
decisions that affect the whole
country. Today, oil provides
most of the country’s wealth, but
shipping has traditionally been
important, and there are major
ports at Abu Dhabi, Dubai,
and sharjah.

MiDDlE EAsT wArs The port at Sharjah is built to
accommodate the most
bitter wars have caused much suffering and death in the Middle modern container ships.
East. israel and its Arab neighbors have fought four wars over
the last 60 years. iran and iraq were constantly at war throughout
the 1980s, and in 1991, NATO and Arab forces defeated iraq
after the iraqis invaded Kuwait. in 2003, American and british
forces invaded iraq and overthrew the dictator saddam hussein.
since 2011, a civil war in syria has killed over 220,000 people.

A statue of the former Iraqi dictator Rebel fighters Find out more
Saddam Hussein is toppled in a square in in Syria Desert wildlife
central Baghdad after the 2003 invasion.
iran
islam
israel
Oil

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