Brahmi, dates back more than 2,500
years. Nearly all the modern alphabets of
India trace their history to Brahmi.
The Cyrillic alphabet was created more
than 1,000 years ago. Members of the
Eastern Orthodox church in eastern
Europe used it for religious texts. The
Cyrillic alphabet was based on the Greek
alphabet of the time. Today people in
Russia, Ukraine, Bulgaria, Serbia, and
elsewhere use versions of the Cyrillic
alphabet.
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Language Writing
Alps, The
The Alps are the youngest, highest, and
most densely populated mountain range
in Europe. They were formed about 44
million years ago. The Alps fill most of
Switzerland and Liechtenstein and
extend into France, Germany, Austria,
Italy, and Slovenia. On the west, the
The word
alphabet was
created from a
combination
of alpha and
beta. These
are the Latin
names for the
first and second
letters of
the Greek
alphabet.
BRITANNICA STUDENT ENCYCLOPEDIA Alps, The 89
Alps run along the border between
France and Italy.
The highest peak in the Alps is Mont
Blanc in France, at 15,771 feet (4,807
meters). Several other high peaks are
located on or near the Swiss-Italian border.
They include the Matterhorn.
The Alps receive a great deal of snow
and rain. At high elevations, the snow
turns to ice and then flows down to the
valleys as glaciers. Sometimes masses of
snow rush uncontrolled down the
mountainsides. These events, called
avalanches, endanger Alpine
communities. The clear Alpine lakes are
noted for their beauty. Among the most
prominent are Lakes Geneva,
Constance, Como, and Zurich.
The Alps are nearly treeless near the top,
but forests grow below. The higher forests
have mostly spruce, pine, and larch
trees. Oak, beech, and chestnut trees
grow on the valley floors and lower
slopes. A few kinds of animals have
adapted well to living in the higher
mountains. These include the ibex, the
Alpine marmot, and the mountain hare.
Humans have lived in the Alps since
prehistoric times, 50,000 to 60,000
years ago. German cultures developed
in the eastern Alps, while Roman
culture influenced the west. Some areas
of the Alps were cleared of forests
during the Middle Ages (500 to 1500).
Farmers settled the land, planted crops,
and raised cattle. During the 1800s,
railroads were constructed, opening up
the area.
Many people began to travel to the Alps
during the 1900s. Air, auto, and rail
transportation to the Alps improved,
making it easier for people to get there.
Today entire villages lodge, feed, and
entertain tourists. Popular resorts
include Innsbruck, Austria; Grenoble,
France; and Saint Moritz, Switzerland.
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Avalanche Europe Mountain
The Matterhorn is one of the tallest peaks in
the Alps.
90 Alps, The BRITANNICA STUDENT ENCYCLOPEDIA
Alzheimers
Disease
Alzheimers is one of the most destructive
diseases of old age. The disease
destroys nerve cells in the brain. As a
result, the brain stops working correctly
and the memory is affected. Most
people who have Alzheimers disease are
more than 60 years old. Some people,
however, get it before that age.
The symptoms, or signs, of Alzheimers
disease begin mildly and then become
more severe over time. At first, people
with Alzheimers seem forgetful. Gradually,
they lose their entire memory.
People with Alzheimers also have a hard
time speaking and understanding other
people. They may not even recognize
close friends and family, such as their
own children. Eventually, they lose control
of body and mind.
Scientists are not sure what causes the
death of nerve cells in the brains of
people with Alzheimers disease. They
think the cause might be a genetic
defect. This means there might be a
problem with one of the genes that is
passed from parent to child. Because the
cause is unknown, there is no way to
prevent or cure Alzheimers disease.
Medications help to slow the disease in
some patients.
Amazon River
The Amazon is the mightiest river in
South America. It carries more water
than any other river. It is about 4,000
miles (6,400 kilometers) long. Only the
Nile River in Africa is longer.
The Amazon begins in the Andes
Mountains in Peru. From there it flows
north and then east through Brazil. It
empties into the Atlantic Ocean. The
Amazon drains about one third of South
America. This area includes most of
Brazil and Peru and parts of Bolivia,
Ecuador, Colombia, and Venezuela.
Plants and Animals
The Amazon region is the site of the
worlds largest rain forest. Its plant and
animal life is remarkably rich. Almost
three fourths of all the types of plants in
the world grow there. The animals
include monkeys, anteaters, anacondas,
toucans, and huge rodents called capybaras.
The flesh-eating piranha is among
the rivers many fish.
People
Millions of Brazilians live in cities in the
Amazon region. Belem, Manaus, and
Santarem are large, growing cities.
The Amazon
River carries
about 10 times
as much water
as the Mississippi
River.
BRITANNICA STUDENT ENCYCLOPEDIA Amazon River 91
At one time almost 7 million Indians
lived in the Amazon region. Europeans
arrived in the 1500s. They took many
Indians into slavery and removed them
from Brazil.Other Indians died from
diseases carried by the Europeans. In the
1990s there were about 600,000 Indians
in the Amazon.Most live in remote areas.
Economy
The countries of the Amazon region
have encouraged businesses to use the
resources found there. Mahogany, Amazonian
cedar, and other trees are cut
down for their wood. Rubber is another
valuable plant product. Diamonds, gold,
and oil are mined.
Many people have become concerned
about the effects of economic development
in the Amazon. Scientists warn
that destroying parts of the forest threatens
the plants and animals that live there.
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Brazil Rain Forest
Amber
Amber is a hard, yellowish, and often
see-through substance that formed from
tree resin. Resin is a thick fluid that
oozes from pine and fir trees when their
bark is injured.
The resin that formed amber came from
trees that grew millions of years ago.
Over time these trees and their resin
became buried beneath Earths surface.
The trees eventually decayed and disappeared.
But the resin hardened further,
until it became amber.
Many pieces of amber contain the
remains of insects or plants in the form
of fossils. These living things were
trapped in the resin before it hardened
into amber. Scientists study these creatures
to learn how living things have
changed over millions of years.
People have found amber throughout
the world. However, most of it comes
from the shores of the Baltic Sea in
northern Europe. This amber is buried
in sands that are 40 million to 60 million
years old.
Ancient people valued amber for its
beauty. They used it to make beads and
carvings. The ancient Greeks and
Romans also believed that amber had
magical and healing properties. Artists
today turn pieces of clear amber into