into gasoline, fuel oil, and many other
products.
In 1856 William Henry Perkin of
England made a breakthrough in the
A steam locomotive called the Dewitt Clinton
hauled carriages on railroad tracks in
the early 1830s.
Thomas Alva Edison holds up an early version
of the electric lightbulb, which he
developed in the late 1800s.
BRITANNICA STUDENT ENCYCLOPEDIA Technology and Invention 27
field of chemistry. Starting with coal
tar, which is made from coal, he
invented the first synthetic, or artificial,
dye. Coal tar and petroleum proved to
be useful in the making of drugs and
plastics as well.
Modern Technology
Mass Production
Modern manufacturing methods can
produce goods in large numbers. This is
called mass production. An important
technique of mass production is the
assembly line. An assembly line product
is put together one piece at a time as it
moves past workers on a conveyor. Each
worker does just one task. In the early
1900s Henry Ford perfected the assembly
line to make automobiles in the
United States.
Later in the 1900s robots began to
replace assembly-line workers. A robot is
a machine that operates on its own.
Air and Space
In 1903 the Wright brothers of Ohio
produced the first successful airplane.
The Russian-born inventor Igor
Sikorsky developed the helicopter in the
United States in the 1930s. At about
the same time Frank Whittle of
England developed a jet engine for
airplanes.
German scientists used rockets inWorld
War II (1939–45). Rocket engines carry
oxygen as well as fuel. This allows them
to work in outer space, where there is no
oxygen. After the war the Soviet Union
and the United States developed programs
to send people into outer space in
space ships. In 1957 the Soviets put the
first artificial satellite into orbit around
Earth. The Americans landed the first
human on the Moon in 1969.
Energy
Beginning in the 1900s scientists found
ways to harness the energy of sunlight.
Solar furnaces use mirrors to focus solar
heat. Solar cells make electricity from
sunlight.
Scientists also found ways to use the
energy that holds atoms together. Atoms
are the tiny units that make up everything.
This energy is called nuclear
energy. It found its first use in very powerful
bombs called atom bombs that the
United States used inWorldWar II.
Scientists soon learned to use nuclear
energy to make electric power.
Electronics and Computers
Electronic products changed people’s
lives greatly during the 1900s. Electronic
A machine in a factory produces polyester
cloth. Polyester is an artificial fiber made
from coal and petroleum (oil) products.
28 Technology and Invention BRITANNICA STUDENT ENCYCLOPEDIA
products rely on electricity to carry or
process information. Radios were some
of the first electronic products. By the
1920s radio programs were being broadcast
into people’s homes. Television, a
later electronic product, came into use
during the 1930s and 1940s. The first
electronic computers were invented in
the 1940s as well.
Later in the 1900s electronic products
became smaller. People discovered how
to fit the parts that make electronic
products work onto tiny chips called
integrated circuits. These chips made
personal computers possible. Other
inventions of the late 1900s also used
integrated circuits. They included compact
disc players, cellular telephones,
digital cameras, and many other electronic
products.
Technology and Medicine
In the 1900s scientists began applying
technology directly to living things. Scientists
developed electrical devices to
help people with disabilities. Some
devices, such as hearing aids and kidney
dialysis machines, operate from outside
the body. Doctors place other electrical
devices inside the body. For example,
pacemakers help keep hearts beating
steadily.
In addition, scientists learned how to cut
and rejoin genes. (Genes are tiny units
within cells that carry information about
a living thing.) This is called genetic
engineering. Genetic engineering may
help to cure human diseases. It also
helps to produce food plants that resist
diseases.
#More to explore
Airplane • Automobile • Bridge
• Bronze Age • Computer • Electricity
• Electronics • Genetics • Industrial
Revolution • Iron Age • Nuclear Energy
• Petroleum • Plastic • Printing • Radio
• Railroad • Robot • Rocket • Ship
• Steel • Stone Age • Telephone
• Television • Textile
Tecumseh
Tecumseh was a leader of the Shawnee
Indians. He fought to keep American
settlers out of the Ohio River valley.
Tecumseh was born in 1768 in what is
now Ohio. His father was a Shawnee
chief. His mother belonged to the
Creek tribe. When Tecumseh was about
A dialysis machine helps a patient whose
kidneys are not working properly. The
machine does the work that the kidneys
would do. Blood from the patient flows
through the machine, where it is cleaned.
The blood then returns to the patient’s bloodstream.
BRITANNICA STUDENT ENCYCLOPEDIA Tecumseh 29
6 years old, his father was killed in a
battle with white settlers. Then
Tecumseh’s mother returned to her
people. An older sister and brother
raised Tecumseh. A Shawnee chief later
adopted him.
Tecumseh spent his life fighting American
