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A telephone is an instrument that sends and receives information, usually by means of electricity. The word telephone comes from Greek words meaning far.

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Presentation on theme: "A telephone is an instrument that sends and receives information, usually by means of electricity. The word telephone comes from Greek words meaning far."— Presentation transcript:

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2 A telephone is an instrument that sends and receives information, usually by means of electricity. The word telephone comes from Greek words meaning far and sound. The telephone is one of our best ways to communicate. In an emergency a telephone can save your life. You can make a telephone call almost anywhere in the world. Telephones are even used in cars, planes, ships, and on lots of different mechanical machines.

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4 While Alexander Graham Bell was experimenting with telegraph instruments in the early 1870s, he realized it might be possible to transmit the human voice over a wire by using electricity Bell's interest in electricity continued and he attempted to send several telegraph messages over a single wire at one time.

5 Lacking the time and skill to make the equipment for these experiments he enlisted the help of Thomas A. Watson. The two became fast friends and worked together on the tedious experimentation to produce sounds over the "harmonic telegraph." It was on June 2, 1875, while Bell was at one end of the line and Watson worked on the reeds of the telegraph in another room that he heard the sound of a plucked reed coming to him over the wire.

6 The next day, after much tinkering, the instrument transmitted the sound of Bell's voice to Watson. The instrument transmitted recognizable voice sound, not words. Bell and Watson experimented all summer and in September, 1875, Bell began to write the specifications for his first telephone patent. By March 1876 he managed to make a transmission, but the sound was very faint.

7 The patent was issued on March 7, The telephone carried its first intelligible sentence three days later in the rented top floor of a Boston boarding house at 109 Court Street, Boston By the summer of 1877, the telephone had become a business. The first private lines, which typically connected a businessman's home and his office, had been placed in service

8 From the telephone's earliest days, Bell understood his invention's vast potential. He wrote in 1878: "I believe in the future, wires will unite the head offices of telephone companies in different cities, and a man in one part of the country may communicate by word of mouth with another in a distant place."

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15 Dr. Martin Cooper of Motorola, made the first private handheld mobile phone call on a larger prototype model in Dr. Martin Cooper

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17 Pairwork A = interviewer B = Alexander Bell Newsflash!! The telephone has been created. Interview Bell for the news.. Writing Write a newspaper report to follow this on..


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