A U B I N A N T H O N Y ; P R E M O R E L L E F A B I E N ; D E L A S C L E M E N C E

THE INVENTOR

The mobile phone was invented in 1983 by Martin Cooper (Motorola Vice President). But beforemobiles, ‘normal’ phones existed.

BEFORE THE MOBILE

In the 17th century : a string phone

In 1667 Robert Hook, physicist written English "using a taut wire, I could instantly transmit sound at a great distance and speed if not as fast as light, at least incomparably greater than that of sound in air ». This principle is the origin of the phone cord that everyone knows. They are constituted by two tubes of cardboard which each have a side closed by a membrane. At the center of each tube, a string is attached to link them.

18TH CENTURY:

THE ACOUSTICS

In 1782 a monk, Dom Gauthey, had the idea to exploit

the acoustic property tubes that transmit sound to

one of their ends. This is the origin of the sound tubes.

The apparatus consists of two wooden tips connected

by a tube with a length of up to a few dozen metres.

The conversation is possible by blowing into the

mouthpiece with a little whistle. The conversation is

then established with the mouthpiece being

alternated from ear to mouth.

19TH CENTURY: THE NAME AND TELEPHONE PRINCIPLE

The name « telephone » appeared in France in 1850 in theBouillet universal science dictionary. It means sound travellinglong distances. François Sudre, a French musician, proposed amethod of telephony which was successfully applied in the armyand navy. It used three musical notes issued by a bugle, drum orbarrel and combined them by giving them a similar value.

And it's a Frenchman, Charles Bourseul, a telegraphemployee, who published in 1854 and for the first time ever, anote on the possibility of transmitting speech electrically:"Imagine that we are talking about a moving plate flexibleenough not to lose any of the vibrations produced by the voice;that plate establishes and interrupts communications with abattery: you may have to distance another plate that will runalong the same vibrations."

Everyone laughed at the time and yet it is largely on that principle that anAmerican successfully operated a telephone 22 years later! For his visionary work, Charles Bourseul wasmade Knight of the Legion of Honour and ended his career as Director of Telegraphs in the Lot.

PERSONS USING CELLPHONES IN THE WORLD

THE RISKS OF CELL PHONES

Cell phones can be dangerous and can cause serious diseases (tumors, cancers ...).

There are also risks of electrocution.

There are about 5 billion mobile phone users in the world

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Summary:

The video is about persons who took refuge within a space preserved from the

waves produced by telephones and Wifi.