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Alexander Graham Bell

March 3, 2012 by · Comments Off on Alexander Graham Bell 

Alexander Graham Bell, Alexander Graham Bell (March 3, 1847 – August 2, 1922) was an eminent scientist, inventor, engineer and innovator who is credited with inventing the first practical telephone.

Bell’s father, grandfather, and brother had all been associated with work on elocution and speech, and both his mother and wife were deaf, profoundly influencing Bell’s life’s work. His research on hearing and speech further led him to experiment with hearing devices which eventually culminated in Bell being awarded the first US patent for the telephone in 1876.[N 2] In retrospect, Bell considered his most famous invention an intrusion on his real work as a scientist and refused to have a telephone in his study.

Many other inventions marked Bell’s later life, including groundbreaking work in optical telecommunications, hydrofoils and aeronautics. In 1888, Alexander Graham Bell became one of the founding members of the National Geographic Society. Bell has been described as one of the most influential figures in human history.

Alexander Graham Bell

February 10, 2012 by · Comments Off on Alexander Graham Bell 

Alexander Graham Bell, Alexander Graham Bell (March 3, 1847 -August 2, 1922) was an eminent scientist, inventor, engineer and innovator who is credited with inventing the first practical telephone.[N 1]

Bell’s father, grandfather, and brother had all been associated with work on elocution and speech, and both his mother and wife were deaf, profoundly influencing Bell’s life’s work. His research on hearing and speech further led him to experiment with hearing devices which eventually culminated in Bell being awarded the first US patent for the telephone in 1876.[N 2] In retrospect, Bell considered his most famous invention an intrusion on his real work as a scientist and refused to have a telephone in his study.

Many other inventions marked Bell’s later life, including groundbreaking work in optical telecommunications, hydrofoils and aeronautics. In 1888, Alexander Graham Bell became one of the founding members of the National Geographic Society. Bell has been described as one of the most influential figures in human history.

Telephone Inventor

February 10, 2012 by · Comments Off on Telephone Inventor 

Telephone Inventor, The invention of the telephone is the culmination of work done by many individuals, the history of which involves a collection of claims and counterclaims. The development of the modern telephone involved an array of lawsuits founded upon the patent claims of several individuals.

This article covers the early years 1844-1898, from conception of the idea of an electric voice-transmission device, failed attempts to use “make-and-break” current, successful experiments with electromagnetic devices by Alexander Bell and Thomas Watson, to commercially successful telephones in the late 19th century.

The origins of the telephone date back to the non-electrical string telephone or “lover’s telephone” that has been known for centuries, comprising two diaphragms connected by a taut string or wire. Sound waves are carried as mechanical vibrations along the string or wire from one diaphragm to the other. The classic example is the tin can telephone, a children’s toy made by connecting the two ends of a string to the bottoms of two metal cans, paper cups or similar items.

The essential idea of this toy was that a diaphragm can collect voice sounds from the air, as in the ear, and a string or wire can transmit such collected voice sounds for reproduction at a distance.

American Charles Grafton Page (1812-1868) in 1837 passed an electric current through a coil of wire placed between the poles of a horseshoe magnet. He observed that connecting and disconnecting the current caused a ringing sound in the magnet. He called this effect “galvanic music”.
Innocenzo Manzetti considered the idea of a telephone as early as 1844, and may have made one in 1864, as an enhancement to an automaton built by him in 1849.
In 1854 Charles Bourseul, a French telegrapher, published a plan for conveying sounds and even speech by electricity in the magazine L’Illustration (Paris). Bourseul’s ideas were also published in Didaskalia (Frankfurt am Main) on September 28, 1854: “Suppose”, he explained, “that a man speaks near a movable disc sufficiently flexible to lose none of the vibrations of the voice; that this disc alternately makes and breaks the currents from a battery: you may have at a distance another disc which will simultaneously execute the same vibrations…. It is certain that, in a more or less distant future, speech will be transmitted by electricity. I have made experiments in this direction; they are delicate and demand time and patience, but the approximations obtained promise a favourable result.”

This make-or-break signaling was able to transmit tones and some vowels, but since it did not follow the analog shape of the sound wave (the contact was pure digital, on or off) it could not transmit consonants, or complex sounds. Bourseul’s phrase “make and break the current” was inaccurately applied to later work by Philipp Reis who successfully transmitted faint voice sounds with unbroken current.

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