History Of Telephone
History Of Telephone

File:Actor portraying Alexander Graham Bell in an AT&T promotional film (1926).jpg|thumb|Actor portraying Alexander Graham Bell in a 1926 silent film. Shows Bell's first telephone transmitter (microphone


Telephone prehistory

Mechanical and acoustic devices

[[File:Trådtelefon-illustration.png|thumb|right|A 19th century acoustic tin can or "lovers' telephone"]]

Before the invention of electromagnetic telephones, mechanical acoustic devices existed for transmitting speech and music over a greater distance greater than that of normal direct speech. The earliest mechanical telephones were based on sound transmission through pipes or other physical media.[1] The acoustic tin can telephone, or "lovers' phone", has been known for centuries.[1] It connects two diaphragms with a taut string or wire, which transmits sound by mechanical vibrations from one to the other along the wire (and not by a modulated electric current). The classic example is the children's toy made by connecting the bottoms of two paper cups, metal cans, or plastic bottles with tautly held string.[1][2]

Some of the earliest known experiments were conducted by the British physicist and polymath Robert Hooke from 1664 to 1685.[1][3] An acoustic string phone made in 1667 is attributed to him.[4]

For a few years in the late 1800s, acoustic telephones were marketed commercially as a competitor to the electrical telephone. When the Bell telephone patents expired and many new telephone manufacturers began competing, acoustic telephone makers quickly went out of business. Their maximum range was very limited.[2] An example of one such company was the Pulsion Telephone Supply Company created by Lemuel Mellett in Massachusetts, which designed its version in 1888 and deployed it on railroad right-of-ways.

Additionally, speaking tubes have long been common, especially within buildings and aboard ships, and they are still in use today.[5]

Electrical devices

The telephone emerged from the making and successive improvements of the electrical telegraph. In 1804, Spanish polymath and scientist Francisco Salva Campillo constructed an electrochemical telegraph.[6] The first working telegraph was built by the English inventor Francis Ronalds in 1816 and used static electricity.[7] An electromagnetic telegraph was created by Baron Schilling in 1832. Carl Friedrich Gauss and Wilhelm Weber built another electromagnetic telegraph in 1833 in Göttingen.

Bell prototype telephone stamp
Centennial Issue of 1976

The electrical telegraph was first commercialised by Sir William Fothergill Cooke and entered use on the Great Western Railway in England. It ran for 13 mi (21 km) from Paddington station to West Drayton and came into operation on April 9, 1839.

Another electrical telegraph was independently developed and patented in the United States in 1837 by Samuel Morse. His assistant, Alfred Vail, developed the Morse code signaling alphabet with Morse. America's first telegram was sent by Morse on January 6, 1838, across 2 miles (3 km) of wiring.


Invention of the telephone

Credit for the invention of the electric telephone is frequently disputed, and new controversies over the issue have arisen from time to time.Antonio MeucciAlexander Graham Bell, and Elisha Grayamongst others, have all been credited with the telephone's invention. The early history of the telephone became and still remains a confusing morass of claims and counterclaims, which were not clarified by the huge mass of lawsuits to resolve the patent claims of many individuals and commercial competitors. The Bell and Edison patents, however, were commercially decisive, because they dominated telephone technology and were upheld by court decision in the united states .