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o History of communications systemso TELEGRAPH Definition Who invented and when it was invented? The working principle Its impacto TELEPHONE Definition Who invented and when it was invented? The working principle Its impact
Printing Typewriter Telegraph Telephone Radio Computer Television Internet Press (1800s) (1837) (1876) (1896) (1897) (1927) (1983) (1400)
Definition: Telegraph (from Greek): tele- means “afar, far off” graphein- means “writing” ▶ Telegraph is aninstrument that transmitsthe writings to a distantplace.
Before the invention of telegraph, there were the signaling systems that people could communicate over the long distance. The signaling systems were called “semaphore” which they used flags or lights. In this system, there was the observer who decoded a signal from a high tower and then sent it to the next station.
In 1832, when Samuel F.B. Morse was in a ship returning from Europe, he accidentally had an idea of using electricity to communicate over distance. Because in this ship, many passengers discussed about the electromagnet which was recently invented. After Morse entirely understood how the electromagnet worked, he realized that sending a code-message via a wire might be possible. However, Morse found that this were difficult. Thus, he asked his friend, Leonard D. Gale in order that he could follow his idea. Samuel Finley Breese Morse (1791 –1872)
In 1837, because of the Panic which caused a long depression, Morse could not introduce his new system although he had enough confidence to do that. However, Morse used this time to travel to Europe not only to register a patent but also to examine the English telegraph systems. He felt very confident because even though his main competitor had created an ingenious mechanism, Morse’s telegraph was more efficient and easier to use. Fortunately, in 1843, the economic was recovering, Morse again asked the Congress for the cash of $30,000 in order to build the underground telegraph line from Washington to Baltimore. Morse hired the great construction engineer, Ezra Cornell to lay the pipe which carried the wire. However, because of the wire was defective insulation, Cornell suggested stringing wires overhead on trees. Morse approved of this great idea. Finally, the line was completed.
On May 24, 1844, the first message, “What hath God wrought?” was sent by the telegraph.Sending the first telegraph message
At first, the telegraph system progressed slowly and the system could not work for the entire country. Thus, Morse continually tried to improve the telegraph system as well as to extend the telegraph line. Fortunately, other companies began to open their own systems, the telegraph system began to develop. In 1914, automatic transmission was developed instead of trained code users that were used in the first telegraph to transmit the telegraph messages. This development in transmission made the message transmission much faster than the old way. At that time, all long distance communication depended strongly on the telegraph. However, when the telephone and radio were invented, the telegraph was less develop than that in first haft of 1990s.
With the invention of telegraph, the world suddenly became much smaller. With the invention of telegraph, the world became more connected. Moreover, the telegraph also contributed to the establishment of world peace by erasing the national–rivalries.
Definition: Telephone (from Greek): tele- means “afar, far off ” -phone means “sound, voice” ▶ Telephone is an instrument that transmits sound, voice to a distant place.
Before the invention of telephone, there was telegraph which was telephone’s precedent. In the early 1870s, while Alexander Graham Bell was experimenting with telegraph, he realized that transmission the human voice over a wire by using electricity might be possible. Because he lacked the skill to make the equipment that were necessary for the experiments, he asked Thomas A. Watson for assistance. Alexander Graham Bell (1847 – 1922)
Bell and Watson worked together on the experience which tried to produce sounds over the “harmonic telegraph”. On June 2, 1875, Bell heard the sound coming to him over the wire. After much tinkering, the instrument successfully transmitted the recognizable voice sound, but not words. Thus, Bell and Watson spent the whole summer to experiment. On March 7, 1876, the patent for telephone was issued to him. At 109 Court Street, Boston, the first Alexander Graham Bell understandable sentence was carried by the was working on the first telephone telephone.
The electric energy isconverted to acoustic energy again The speedy conversion from acoustic to electric energy
At first, the telephone was extremely hard for anyone to afford because of its price. Only the rich could afford for telephone. Telephone’s invention contributed to the development of city centers and buildings. With the invention of telephone, some jobs suddenly became unnecessary. In addition, the world became much smaller and more accessible to all business because of the telephone.
Time Quantity of telephones (unit)May 1877 6November 1877 3,0001881 133,0001990 600,0001905 2,2000,0001910 5,800,000 The statistic about the growth of telephone
In 1885, American Telegraph and Telephone Company (AT&T) was formed. The growth of telephone was extremely fast. (By 1900 there were nearly 600,000 phones in Bells telephone system; that number raised to 2.2 million phones by 1905, and 5.8 million by 1910). (30 millionth phone was connected in the U.S. by 1984, by the 1960s, there were more than 80 million phone in the U.S. and 160 million in the world).
Nowadays, the telephone is an indispensable instrument on over the world. Telephone makes the world smaller and bring people closer together, thus, decreasing loneliness and building new communities. The invention of telephone also increase privacy in many ways. It allows people to exchange information without writing. Moreover, telephone help people to connect very fast regardless to their distance.