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الکساندر گراهام بل

الکساندر گراهام بل

Alexander Graham Bel :: Alexander Graham Bel

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Alexander Graham Bell

The Victorian period was a time of many new inventions. Earlier discoveries, such as the steam engine, the screw propeller, the power of electricity, and the possibility of sending messages along a wire, were now applied to everyday life. Inventors such as Thomas Edison and Nicholas Tesla explored new methods for harnessing electric power. Some of the greatest discoveries were made by Alexander Graham Bell.

Bell was born in Scotland in 1847. Both his father and grandfather taught speech methods and worked with deaf and dumb children. Alexander was also interested in this work, especially as his mother was almost deaf. Alexander’s two brothers died of tuberculosis, and he himself contracted the disease, so his parents decided to leave Scotland for a drier, healthier climate. They moved to Brantford, Ontario, Canada, and lived in a roomy, comfortable house overlooking the Grand River. Today, the Bell Homestead is an historical museum that attracts visitors from all over the world.

At that time, Canada did not have a lot of business opportunities, so Alexander found a job teaching speech in Boston, U.S.A. But he returned to Brantford every summer. In Boston, Bell married one of his deaf students. His father-in-law suggested that there were good business opportunities in inventing communication devices. Bell soon developed a method for sending more than one telegraph message at the same time. While working on improving the telegraph, Bell and his assistant, Thomas Watson, found a way to send the human voice over wires. On August 10, 1876, Bell sent the first telephone message over wires strung between Brantford and Paris, Ontario – eight miles away. The telephone caused an international sensation, with government leaders asking to have one. But Bell didn’t stop there. He worked on the recording properties of wax cylinders and other approaches to flat phonograph records. He also developed the photophone, which later led to the development of the motion picture sound track.

Bell worked on these inventions at his laboratory in Washington, D.C., but he didn’t like the hot humid summer weather there. So Bell began looking for a new place to spend his summers. He decided to build a summer home in Cape Breton Island, Nova Scotia. The Island reminded Bell of his native Scotland.

Now he had space during the summer to do experiments outside. He soon began to experiment with flying machines. Bell designed and tested huge kites, hoping to come up with a frame for a flying machine. Along with some enthusiastic friends, Bell also experimented with airplanes. On February 23, 1909, one of these planes flew through the air for half a mile. This was the first airplane flight in the British Empire. The Alexander Graham Bell Museum at Baddeck, Nova Scotia, displays many of these inventions.

Bell was also interested in making a faster boat. Since much of a boat stays under water, the water resistance slows the boat down. Bell thought that if you could raise the boat out of the water it would go much faster. Working on Cape Breton Island, Bell and his friends developed the hydrofoil, a boat that would skim the surface of the water at high speeds. Hydrofoils are in use in many places today.

Every time people use the telephone, listen to a recording, watch a movie or television, or ride on a hydrofoil, they owe a debt to that great inventor, Alexander Graham Bell.



Screw propeller

screw_propeller
Device with two or more blades that turn quickly and cause a ship or an aircraft to move forward

Harness

harness
Source 1
To control and use the force or strength of something to produce power or to achieve something
Attempts to harness the sun’s rays as a source of energy
We must harness the skill and creativity of our workforce.

Source 2
To control and use the natural force or power of something:
We can harness the power of the wind to generate electricity.

Tuberculosis

tuberculosis
Source 1
A serious infectious disease in which swellings appear on the lungs and other parts of the body

Source 2
A serious infectious disease that affects many parts of your body, especially your lungs [= TB]

Contract

contract
To get an illness
To contract AIDS/a virus/a disease
Two-thirds of the adult population there has contracted AIDS

Roomy

roomy
Source 1
Having a lot of space inside
Synonym: spacious
A surprisingly roomy car

Source 2
A house, car etc that is roomy is large and has a lot of space inside it [= spacious]

Overlook something

overlook
Source 1
If a building, etc. overlooks a place, you can see that place from the building
A restaurant overlooking the lake
Our back yard is overlooked by several houses.

Source 2
If a house, room etc overlooks something, it has a view of it, usually from above:
Our room overlooks the ocean.

String something + adverb/preposition

string
To put a series of small objects on string, etc; to join things together with string, etc.
Synonym: thread
She had strung the shells on a silver chain.
(figurative) carbon atoms strung together to form giant molecules

Source 2
To hang things in a line, usually high in the air, especially for decoration
String something along/across etc somethingChristmas lights were strung from one end of Main Street to the other.

Wax

wax
Source 1
A solid substance that is made from beeswax or from various fats and oils and used for making candles, polish, models, etc. It becomes soft when it is heated
Styling wax for the hair
Floor wax
Wax crayons
Wax polish

Source 2
A solid substance made of fat or oil and used to make candles, polish etc:
Wax crayons

Cylinder

cylinder
Source 1
An object shaped like a cylinder, especially one used as a container
A gas/oxygen cylinder

Source 2
The tube within which a piston moves forwards and backwards in an engine:
A four-cylinder engine

Photophone
photophone
Enthusiastic

enthusiastic
Source 1
Feeling or showing a lot of excitement and interest about somebody/something
An enthusiastic supporter
An enthusiastic welcome
Enthusiastic about somebody/somethingYou don’t sound very enthusiastic about the idea.
Enthusiastic about doing something She was even less enthusiastic about going to Spain.

Source 2
Feeling or showing a lot of interest and excitement about something
Enthusiastic about (doing) somethingAll the staff are enthusiastic about the project.
The singer got an enthusiastic reception.
An enthusiastic supporter of reform

Hydrofoil

hydrofoil
Source 1
A boat which rises above the surface of the water when it is travelling fast

Source 2
A large boat with wing-shaped parts on the bottom that lift it above the surface of the water when it travels fast [↪ hovercraft]

debt

debt
Source 1
The fact that you should feel grateful to somebody because they have helped you or been kind to you
To owe a debt of gratitude to somebodyI would like to acknowledge my debt to my teachers.

Source 2
The fact of being grateful to someone who has helped you:
I owe a debt of gratitude to my tutors.